Reading the comments I like the idea of running an air compressor best. You could put the tank under water to get your heated fluid. Then you have free compressed air to get cooling or run other contraptions. Magnetic induction is certainly the most efficient way to heat the water, but I suspect efficiency isn't your only aim with this project!
Robert Murray Smith has made videos for what is called a friction "frenette" Where oil is heated between a rotating cylinder and another cylinder Budget option
@@wayoutwest-workshopstuff6299 If you want to try inductive heating, I think you could affix diametrically magnetized neodymium ring magnets to an aluminum shaft, place this coaxially inside aluminum tubing using stainless steel bearings (to avoid galvanic corrosion due to current flow), and place the whole assembly inside PVC pipe where the water will actually flow. This will keep the mechanism sealed away from the water and the aluminum tubing should work as an optimal shorting ring since the magnet is fully enclosed by it. To maximize the coupling you want the gap between the magnets and the aluminum to be as small as possible. Magnet strength, number of magnets/length of shaft and gap clearance can be adjusted to optimize the load for the drive mechanism. Because the bearings are also in contact with the aluminum pipe, their waste heat should also transfer to the water.
Probably an old torque converter would be ideal. Just stall the output impellor and use the inbuilt pump to circulate oil to your heat exchanger primary circuit.
A very similar device that's actually designed to have water as the working fluid and for converting mechanical power into heat is a _water brake dynamometer._
I suggested one of the drums, then realized the whole transmission and tq converter. Fill with water, turn the input, lock the output. Water to water intercooler through the trans cooler lines. Gave ya a thumbs up for getting here first lol
Worth a shot, even if the heating is not satisfactory, it could be used as a progressively adjustable brake by varying the fluid level in the converter
The issue with solid on solid friction is that it would wear down leaving particulate in the water and increase the required maintenance. I'm aware that the title is the practicality of it, but it might be more efficient to run a generator to power a heat pump. For even more efficiency you'd need to cut out the electricity and use a mechanically driven compressor but that's even less practical. Just a fun thought.
A compressor is a good idea as an answer to the question of how to convert mechanical energy into thermal energy! When air is compressed, it becomes warm. This compressed air is passed through a long spiral tube surrounded by water. ==> Water gets warm too.
That particulate is why I'd be concerned about this ever being used to heat water for drinking. Using electricity to do the boiling will likely have a much lower energy loss, if you do the heating beside the house, and transfer the electricity over a distance it should be ok and space shouldn't be as much of an issue. The earth tends to be a pretty good insulator too, so such a boiler could be next to the house, under a paddock, or pretty much anywhere.
Multiple layers of paddles spinning between paddles that don't spin (stators) cause 'shear' in the water. That creates a lot of heat. Think of an automatic transmission, except with the pitch of the blades and stators being straight. One fellow here recommended turning a heat pump, and that's an excellent idea.
Yeah a heat pump is ideal here. Could also be an air conditioner in the summer with just a couple extra valves. A car AC compressor as proof of concept and if it works well you can look for a commercial shaft-driven refrigerant pump surplus/craigslist etc.
The absorbers used on water brake dynamometers are simple and have no wearing surfaces. They are designed expressly for converting kinetic energy into heat. Worth investigating I think.
@@wayoutwest-workshopstuff6299 ua-cam.com/video/nSNkB0BXnHM/v-deo.html i don't know if you can manufacture something like this in your workshop but the computer voice explains it good and the animation makes sense immediatly!
@@wayoutwest-workshopstuff6299 This is the way. You just need to direct your energy to move the water. Restricting water movement will build you the proper torque to regulate the system to your suitable rpms. I would try using a submerged pump and recirculating circuit. The same pump can also supply you the water for consumption.
Tim, noncontact is probably the way to go. if magnets and induction are too high tech, Then something with viscous fluid being forced through some torturous path. I also suggest considering a heat pipe to move the heat around. You can make one easily! put a little water or other appropriate fluid in a capped pipe until it boils and then close a valve on the other side to seal the pipe and liquid at low pressure. In use the water boils at low temperature and the steam communicates the heat to the end of the sealed tube. A great pumpless way of moving heat. It’s very very efficient. Of course placing the entire heat generating mechanism in a large tank of water will work also, but the heat pipe is a good trick.
Pumping fluid around needs pumps, and they have friction with the vanes / impeller / whatever, and the liquid. You can't avoid wear. Heat pipes AFAIK are used mostly in computers where you need to shift a lot of heat quickly in a small space, do there exist great big ones? Since this is for domestic bulk heating, just using chunks of metal, ideally copper, seems better. Heat pipes are for when removing heat is the priority.
Generating electricity to power a heat pump would allow for heat to be extracted both from the air, and also other sources (such as the engines, and furnaces used for processing your wood, and of course the surrounding air, and if practical, under the ground). Friction is certainly an 'interesting option', but I fear that it is rather limited in scope, and rather high in maintenance and consumables - efficiency not really mattering in this case (so I discount it here). Interesting project - which is asking great questions!
I posted another comment about this, but I think a car AC unit is an interesting option. They are designed to use the engine's rotation to power the compressor, which means you wouldn't need an electric generator.
@@MrAwawe Yeah it's probably worth a try. I'm not sure how long you can get a compressor to last, but you definitely need to pay attention to the oil and making sure there's enough, and that it can make it's way home to the pump. You really need to turn them pretty fast to work well, like 1500+ rpm (they are always overdriven by the crank pulley).
I had a similar thought in terms of using a heat pump but think it does not need the complication of converting the energy to electricity to then power the pump(s) and instead they could be direct drive, requires some gearing and either there would need to be a way regulate the stored heat so that if the pump worked continuously it was not a problem or a way to disconnect or regulate the pump once the required temperature is reach which admittedly would be more easily achieved with electrical regulation rather than mechanical.
The VM Motori engine in my car has a viscus heater that takes power from the fan belt and spins a binch of closley stacked plates with a super thick goo between them. Water flows through an isolated channel to absorb the heat. I know it's probably cheating, but it's an off the shelf solution.
in an ICE that just makes no sense when 1/3rd the energy is getting dumped out the cooling system, and the other 1/3rd being dumped out the exhaust pipe...
His current design isn't too far off from being one other than having plates touch. It just needs holes in the rotor plates as initiation sites for cavitation, correct spacing, and perhaps more RPMs.
This WAS a great experiment! I don't know anything about friction and heat loss and if it would work. But thats why you're here. I'm sure we're going to find out! That's the super fun part. P.S. Don't get sick, Tim. Thats no fun! 🤪
There was a program in the 80s or 90s called it runs on water. One inventor used a cylinder full of holes strategically placed and rotating to heat water.
This is an interesting experiment and your videos are great! One option might be to couple the mill to a pump and pump the water through small holes rather than small holes moving through water. You could possibly bring the heater to your house with hoses and have minimal loss on the way.
If you used oil as a medium to reduce wear, then added a spring to create end pressure. The spring pressure could be adjusted by a flyball governor to regulate the wind shaft speed and ease starting in low winds, cheers
Noise and plate wear are the biggest issues, as well as contamination of the working fluid over time with plate material which would gum up anything you try to pump this into. Still, an interesting experiment!
Very interesting Tim, I had no idea there were so many ways of heating water via mechanical input. As per other comments my instinct would be to generate lovely useful electricity but suspect that doesn't fit the ethos of the project. After all, that would end up being another wind turbine on a stick, and you've already done that! Anyway, I like the idea of storing a few tons of warm water, although where you could get it, I don't know: your part of the world has always struck me as being particularly dry ... All best wishes from East Sussex.
Hi Tim, hope you're okay with your cold and have a speedy recovery! For our plasma cutter we have a twin moisture trap setup. One at the compressor and one at the back of the plasma cutter. It usually works okay whatever the weather.
Just throwing off one-off ideas... A permanent magnet alternator like such in a motorcycle in oil bath with the outputs wired directly through resistors, either in the said oil bath or the adjacent water tank. The stator coils on such an alternator will get pretty damn hot as all the excess energy that's doesn't end up in the resistors as useful electric current would just be dumped into the oil as thermal energy. And if we cooled the oil by exchanging heat with the water tank the total efficiency would be pretty high. No controller needed, no fancy conversions, just three AC outputs from the alternator directly heating the water and if things get too hot and the temperature and the pressure of the water tank would rise enough a safety valve could purge hot water out and a one-way inlet valve could let cold water in to cool down the tank (and thus the alternator oil bath). You could probably find such alternators for pennies from the junk yard and you could scale the unit up by attaching multiple to the same shaft. No physical metal contact besides bearings so the oil would remain clean for a long time.
Heat pump ! :) Direct drive on a compressor from an old fridge : that will be interesting. And you get a cold source at the same time to keep some food.
yeah sounds like a good idea. however a fridge only has a max of 2kw? maybe even only about 200watt. house heating will easily use 10kw. so you would need 50 old fridges.
@@schirmcharmemelone a resistiv electric water heater is 2kW yes. But a heat pump will use a third of that. A 200 W compressor from a fridge will fit the windmill :)
As I’m sure you’re already aware, this is the same method James Joule used to determine the relationship between mechanical power and heat energy. It might be interesting to use this setup to measure how much power your windmill generates?
Hi Tim. For storing thermal energy at low temperatures, you should look at phase change materials. The energy is locked up in the material as it changes phase from solid to liquid. The energy is released as it changes back from liquid to solid. A good choice for your application might be sodium sulfate decahydrate.
bacon grease has a good solidus to liquidus temperature range (approx 85 to 130F) and can be sealed in mason jars in a holding thank. also you can enjoy a lot of BLTs while you amass the grease.
@@makingitthrough190 They're basically compressors, which are basically pumps. You could knock something up at home, and even if it's not optimal, just having a heat pump at all makes it easy to be super-efficient. Getting a professional system is an option and then you'd be able to use it on normal mains electricity as well, the DIY system would also have to supply electricity to it. If you're making it cheaply out of scrap, though, it seems like as good a use of your time as any. You'd put a loop of piping down in the ground, or else just use air-sourced to start with. Then once it's installed, you leave that, and only tinker with the moving parts indoors and above-ground.
Cool experiment. But I’m really enjoying the comment section. Some really great ideas. One that I found partially interesting was having a copper coil with water running through. Fire is often the way to go with this method but maybe friction or magnets in this scenario might work. Also, fire could work but use the windmill to pump air into the fire, like a forge, to super heat the fire, and heating the water much faster. More of a hot water on demand situation. Also really like the compressor idea, where you could go with a heat pump type situation. Great stuff! Look forward to seeing where you go with this. Keep experimenting!
I have always loved the idea of using a windmill to get heat through friction. In theory the efficiency can be really high. The heat can be easily stored for some period of time. It's a challenge to match speeds and forces though, and variablitity would be great. In your setup, I'm pretty sure you can get heat through fluid friction alone without the plates wearing. Couldn't you make an inefficient pump forcing fluid through cntrollable contraints? Anyway, I'm guessing water-brakes are a pretty well-established industrie. I'm happy to be sponsoring this project.
High speed blenders cook soups using the same physics but the friction is made by moulding ribs in the wall of the 'paint can'. Of course this would cause wear in the holding vessel which couldn't easily be replaced. I wonder if you can just have a spinning shaft creating a vortex in a smooth vessel - but have vertical rebar rods staggered throughout to create the friction. When they get consumed then it would be easier to replace with off the shelf parts than having to fabricate new plates. Would probably be trading efficiency for convenience though
When making aluminum ships, sometimes the seams are 'friction stir welded'. We went to the navy shipyard to see it being done when I worked at the shipyard. Did you factor-in the cost of the steel? How fast would the steel wear away and need to be replaced? 🤔 How about driving a heap pump to cool and heat?
Hi Tim, how about now trying to power a heating element with an old car alternator driven by the drill, measure the energy required to power the drill to raise a fixed amount of water by a fixed amount. Then compare to the friction method. Then you will have reliable data on which is more efficient 👍 great vids, keep them coming!
I was thinking the same thing. It would be interesting to know whether the friction method is more or less efficient than the electric method. I think the electric method would have more benefits though - no mechanical link needed between the windmill and the heater, minimal wearing of parts, ability to heat water directly without heating oil and using a heat exchanger, ability to use alternate energy sources other than wind, and so on. The only drawback would perhaps be the cost of the generator/alternator, but then you'd need less plasma cut metal plate so maybe it would work out much the same?
Theoretically, the friction method is more efficient because all of the energy is converted to heat. With an alternator, the alternator is going to lose efficiency due to friction and that can't be submerged as easily, reliably and cheaply as just some friction plates to be able to sink the alternator heat back into the system as useful heat. The nice thing about the friction method though is that 100% of the energy put into the system is put into heating the fluid. Then it just becomes a question of if the fluid can handle more heat, if your insulation can retain it, or if you can actually make use of it with whatever the secondary system is. But all of those variables would remain the same no matter what method he uses.
@@doggfite Some good points there. Alternator friction would surely just be in it's bearings, the friction method in the video would need bearings in the final design too. Thinking of the bigger picture my idea was that there will also be a fair bit of energy lost in any angle drive at the top of the windmill whereas an alternator could be mounted up there meaning no need for those losses, just minor losses in the electrical transmission. Braking system is another story!
@@doggfite You'd need a bearing up on the windmill blade though which would be the same whether you're electric or friction. After that you might get a small amount of air resistance on the friction shaft and likely a lot of noise which both reduce the amount of energy that can be converted to heat, and which are both not losses in the electric version. I really think it would be a pretty close call.
direct heating with friction... all the energy contributes to heating. using an alternator... the amount of energy appearing in the resistive load is a ratio between the load and the generator resistance. at best, you get 50% of the applied power into the resistor, when the resistances are equal. the generator will absorb the other 50%. yes, the turbine will deliver twice the power as what you read in the load resistor... if you just short the generator, all the energy appears as heat in its windings. the current will be limited by the wire sizes and magnetic fields... if the load is higher in resistance, more heat appears in the resistor than the windings, but you cant "push" as much power through that resistor, that circuit, anymore, as the current is limited... you deliver less power overall. so rewind an alternator with 3/16 copper pipe, shorting each phase to itself... no worry about star or delta... and tickle the field windings with a voltage appropriate to wind speed (tip speed ratio, actually...) so as to apply a load that is directly proportional to the energy in the wind. which increases on the cube of the velocity. yes, that needs an external power supply. easier to make a retarder... permanent magnets, conductive disc, variable airgap. use a centrifugal governor to control the airgap and the braking force... conductor gets stinking hot. add coolant... you need a load that increases as the wind picks up. pumps, generators, whatever... they all have a fixed amount of power required to simply do what they do. a wind mill takes so much to grind grain, to lift a plunger full of water on every revolution, to deliver so many amps at so many watts into a load... and thats it. they do it faster, it takes the same amount of power to do what they do. yet as they speed up, the wind applies more power, produces more torque... so we have to feather the blades or apply brakes! rather than USE it, we LET IT SLIP PAST. and to make grid-connectable AC voltage at 50/60 hz from the wind directly? HA! that simply doesnt work. at all. if all you do is make heat, you can "hold the brake on" harder, and that just makes more heat! can limit blade speeds, stay in the peak of their efficiency curves... the temperature reached is a matter of how many watts are delivered and how many are dissipated in any given volume... obviously as wind speed picks up things get hotter... much hotter! what can you do with hot water? hmmmmmm.... steam turbines? hot showers? i need a shower... pong.
This is a great idea because heating water with a windmill using electricity will lose ~ 70% of the energy heating the generator. For your application you want to turn 100% of the power from the windmill into heat, and the power of the windmill will vary widely over the course of time. I think you want a friction brake like a disc brake or a drum brake and then have a governor apply enough brake to keep the windmill turning at a reasonable speed. If you use a weighted brake the brake force will be the same when the wind is blowing lightly or very hard - you'll get nothing when the wind is light and you'll miss a bunch of energy when the wind is strong.
This kind of heater exists in mass production in cars, its called a viscous heater, used in some mercedes cars, its filled with a high viscosity oil heated by spinning plates, in order to preheat the coolant in a diesel engine on a cold day and bring cabin heat on faster. Could be inspiration for a more efficient design! Cheers
At the start I was like this is madness, at the end was like this has potential. Makes sense, a large magnet could trap the steel particles in one place for removal as the plates wear out.
Hello Tim, they still make oil impregnated wooden bearings for use in sewer plants and other under water applications. Something that could come in handy, cheers.
Depending on what you want the water for, it may be worth making a heat exchanger, where you've got water in pipes, and water in the heater, but they don't actually mix. This would make it easier to swap out the heating element as needed, and prevent the risk of additional contamination
@@wayoutwest-workshopstuff6299 way less maintenance. no wear. you can make anything a magnet with an electronic magnet, all you need is a copper coil and some DC electricity. just imagine the rust water you will generate. and then the iron is in water all the time. i watched all your videos in the span of a few weeks and saw all your projects rust away after a few winter. insane how rusty stuff becomes in your area so close to the sea! Another alternative would be to use break disks. They are designed for this task. But if you ever looked at the wheels of a used car all that dark brown dust is the old break disk turned into a powder! do we really want to fine grind so much metal into dust? From the amount of comments suggesting magnet heater. you surely can ask some high performance nerd from the comments to calculate all the hard stuff for you :P you just need to ask in a video nicely :P
@@schirmcharmemelone He said in the video he was planning to fill the container with oil so as to avoid the rust, and use a heat exchanger to transfer the heat across to clean water
@@wayoutwest-workshopstuff6299 you would not need to use a heat exchanger. Just a spinning plate of magnets and a metal plate in the tank. No plates rubbing and deteriorating in the water.
@@Berkeloid0The problem isn't rust, but the basic steel against steel friction that will occur. It's an interesting experiment but those plates would be larger, more expensive, and the forces between them much greater in the actual machine.
Interesting experiment! I was genuinely surprised to see that it actually produced such promising results. I wonder if ceramic plates would work even better? Thanks for sharing.
Something to also consider: windmills can self-destruct in high winds due to excessive rotational speed. If your churn-gadget is equipped with a mechanical pump whose pumping capacity scales with rotational speed then as the windspeed increases so does the pump which fills the churn with deeper and deeper water. Your paddles/disks will need to have an air gap (the hard part) so that when in air there is minimal heating, but as the water level rises more and more paddles are covered with water and begin producing heat. All that energy dissipation adds to the resistance to turning which in turn moderates the windmill keeping it from self destructing. A Nice feedback loop. A dual viscocity oil would seem to also be a very good option as the shear increases so does the viscocity and power generating potential. BTW, a neighbour had come up with a very similar idea as this about 40 years ago, but as far as I know never implemented it. I do like your "well, let's give it a try" attitude!
Why not use air compression as a source of heat. Notice how hot a plastic bicycle pump gets when inflating a tyre. Use a few immersed in a water tank by way of heat exchange and connected by a crank. Any air produced can pressurise the water tank (obviously with a relief valve) to provide a pressured warm/hot water supply without the need for an extra water pump.
if you can find a local engineering company with a surface grinder they could stick your plates up and grind them perfectly flat and smooth. oil would definitely be good. really interesting project, following!
there was a device a few years ago that used cavitation. the collapsing "bubbles" produce the heat. It used a drum with dimples in the outside surface.
Hey Tim i saw an interesting idea to do the same thing. A rotor with dimples offset in a tube. This was all under water As it spun it created cavitation in the dimples as it went from low pressure to high pressure
Brilliant! Once enough friction occurs, you may have metal particles in your hot water. How about some sort of heat exchanger to keep the metal separated from the water?
Hello Tim, good questions you are asking. If it were run in a oil, that could help smear it and have less wear maybe. In water and if not much air got to the plates, that also could be somewhat better? Like how you go about with your projects, always nice to see various methods from the regular viewpoints. Thanks and cheers 👍💪✌
Every windmill has a certain ratio of windspeed to rpm where it is most efficent. That means that if you want maximum power you would always have to adjust the rpm to the current windspeed. The good thing about a load like a paddle where the torque that the water created is proportional to the rpm squared is that it controls the rpm by itself that it follows the points of maximum efficiency of the windmill by itself. As long as you just set the gearing and paddle sizes optimal for one windspeed, it will be optimal for other windspeeds too. Hope that was understandable
I like this idea as a direct way to generate heat directly via the rotation of the windmill, but I feel like there's a few issues that could make it unfeasible on a small scale. Corrosion - if you have mild steel plates in a heated, wet, environment would they rust very quickly? And if so, what effects would all that rust particulate have on the system? Especially if you plan to pump the water into radiators. Stainless plates might solve this issue but I imagine they'd be prohibitively expensive. Wear - with a mild steel plate I don't think they'd last long before they'd begin to wear, especially if they're heated and going rusty. You'd then need to constantly adjust the pressure on the plates as they wear thinner to maintain friction as the plates reduce in size. This wear generates more particulates as well. Torque - if you scale up the heater large enough to heat the body of water required to heat a house, Will the windmill have sufficient torque to drive the bigger heater? I'm assuming larger plates would increase the necessary torque exponentially. If you switched to an oil system rather than water, it would solve the rust issue, and aid in reducing wear, but the oil is more viscous. More viscous oil could further increase the torque required to spin those plates, again increasing demand on your windmill. Demand - if the windmill isn't spinning fast during a time of peak demand for heat, then there's suddenly no heat. Is the wind in winter enough to rely on for heating? I think a water brake system with paddles seems easier to build and maintain, as well as more easily scaleable to the size necessary to heat a house. I know it doesn't fit so well with the ethos of your project but turning an electric generator instead of all those ideas seems more efficient, and far easier to build/maintain.
Friction vs. Shear Force - I've had a car with an auxiliary water heater powered by the drive shaft - it was said to use shear forces in liquid to generate heat. It would be interesting to see if you could generate the same amount of heat as before even without the plates touching if you cut elongated slits into both rotor and stator plates. That way you could minimize wear & tear on the plates.
Perhaps a sand battery would be your cup of tea? You should be able to heat sand with friction too, and you could just run some length of copper (water)tubing through your sand battery to create a heat exchanger.
This is a very clever idea, but I can immediately see some problems with it: 1. having metal-on-metal contact with the explicit purpose of friction is going to chew away the plates. This will 2. fill the liquid with metal particles, necessitating regular replacement of that liquid. (I am glad you mentioned using a liquid-to-liquid exchanger; this stuff would not be good to drink.) You're still going to have to add a filter before the exchanger, thought, lest you fill it full of rust. 3. The warmer you run the water, the more of a wearing issue you're going to have; the higher the temps, the easier it is for steel to rust when in contact with water. This makes me think using an oil would be a better choice. (I don't know how using an oil would change the ability to generate heat though.) 4. I'd be interested to see if the heat generation keeps up over a longer period; as the plates wear, they should 'bed' into each other, reducing the amount of friction generated to some degree after the 'break-in' period. My gut says that one of the designs you showed earlier int he video would be a better way to go about it; while direct contact would heat the fastest, it will have a number of maintenance concerns. Still, I wish you luck!
@wayoutwest-workshopstuff6299 not sure it will. You'll probably need an additive package of corrosion inhibitors. Tried this on a machine at work last year...it's surprising how churning water in system with a low open area picks up oxygen very quickly. I changed to 50% glycol.
Running a centrifugal water pump with the circulation through a small venturi will heat the water, and the small venturi will stop the ceramic bearings from overheating. You will now have a pressurized holding tank and pressure will reticulate your water, also now you will have a low pressure feed line into the pump to supply the whole system.
Many years ago, a farmer in the US made a shed with pieces of Fresnel lens, from an old lighthouse, in the roof directed at a drum of water. Even in moderate light this would boil water for a steam generator. He ran a large farm off of electricity/batteries. He used early batteries that were practically indestructible.
Hi Tim, what a nice experiment!! I have go off at a good start. Love to follow your path with the windmill construction to create energy to heat your house. Comming from holland windmills have always been of intrest to me 😊
Hi Tim, I have an idea. You could use thinner plates, they would still be strong enough, but you'd have more surface area of friction in the same space occupied by the bigger plates. I think you get what I'm saying.
The particulate sludge/slurry that would build up would become a problem fairly quickly, I think, and would itself speed up the degradation of the disks. It would be worth seeing how much thinner the disks had become during your testing to estimate how long they would last, and/or you could test the specific density of the water to figure out how much steel was getting into it. I would echo the other people in the comments saying that a heat pump might be the best thing to power with your windmill, although I appreciate that it's not a cheap DIY solution unless you want to try to build one yourself!
Quite a long time ago, there was a company trying to get investment in a 'revolutionary' water heater - it consisted of a solid metal cylinder on an axial spindle. The curved surface of the cylinder was drilled with many shallow cavities and the whole thing was enclosed in a reasonably close fitting cylindrical jacket. Water was passed through the apparatus as an electric motor spun the cylindrical rotor at high speed. It heated water quite effectively, supposedly some pressure effect of the cavities all over the surface of the rotor. The inventor was claiming that it generated more heat than could be generated by the electrical power consumed, which is instantly suspicious, as this device did not seem to be any kind of heat pump. I don't know what became of it. Maybe the whole thing was a scam.
I was pleasantly surprised at the amount of heat it generated. But do those plates actually have to physically rub against one another ? - I'm thinking - supporting the "stator" plates at their edges, and the "rotor" plates being supported in between the stators by washers or short pieces of metal tube on the shaft, preventing any of the plates from touching one another. You might be able to have the plates in close proximity without touching with perhaps just a few mm of water-filled spacing between the moving and non-moving elements if you can get the plates and spacers snug enough so there's not too much play in them.
Very interesting, i was quite impressed by how quick the water warms up. I think you would probably have to have an indirect system whereby this heated water would be pumbed through a pipe through the main cylinder of water. Thus you would avoid contamination from metal filings from the friction. I know this would complicate things somewhat. I wonder if using different metals would make any difference to the process?
Well done Tim - interesting experiment. I think that the one major problem is the wear factor on the plates - are there other materials that culd be used to overcome this?
for the kettle crowd. using a generator to run a heat pump is a more efficient way to heat water. you can move 3-4 times the heat that resistive element creates.
Some years ago I saw a system where a horizontal cylinder had rows and rows of divots drilled into it spaced fairly close together. This was contained inside a steel drum that had lots of divots drilled on the inside, facing the cylinder. They were both within a few millimeters of each other. The cylinder was spun at speed inside the drum with water in between. Something to do with cavitation I think. It was extremely efficient and produced huge amounts of very hot water. The divots looked like about 25mm and 10mm deep.
Maybe dig a hole & put your friction heater in, soil acting as a low cost insulator for heat & sound, top up water as needed via surface tank using a level indicator, & extract via a heat exchanger. As you don’t need high temperatures for central heating water would be fine & also as it’s normally windy where you are you can get away without storage. Probably after a while you will ignore the noise of the wind mill & it would be off for about six months during summer when you don’t want house heating, although you could kiln dry wood or do other jobs with the heat when not needed to heat the house. Thanks for sharing!
Dig a big hole. fill it with insulating layer of styrofoam etc. then a big layer of sand to keep heat. then the water tank with the friction heater inside.
Ok I'll admit that I have never really thought of this. But, I do have a couple of ideas. Such as using a sand battery for storage maybe ? Each climate things work differently with. Here in Arizona USA it is a very dry climate where there in Ireland is definitely a wet climate. We do have a winter not much of one but, it does get cold at night especially. We do get a couple of snow storms but, nearly no build up of snow. We have had snow but, it never stays for more than a day but, that still doesn't mean we don't get cold and night time temps are rather cold. I've knocked around the used oil stove idea because we do have a fireplace and, I'm attached to my walker these days so collecting wood is not going to happen. Being young and unable has some disadvantages you know. Anyway I'm curious how long the metal plates would last but, I like the idea of using oil in it. Keep working on it and I'll keep watching. My projects are trying to build a wind generator for my friends cabins he's getting ready to build. I like the idea of a versicle windmill because it seems that it would be a better for where i'm at. Good luck ahead I love your channel !
That's quite significant heating for something you made it look like you more or less "throw together" in the video. I do agree with other comments that induction would have a big advantage for long term use, but obviously that would require a lot of magnets, that can handle the temperature, some magnets starts to loose their magnetism at temperatures well below 100 °C, and if the system happens to run dry for any reason 100 °C is no longer the limit. Personally I'd might go with a belt driven air compressor to generate heat. The vast majority of the power a common air compressor uses turns into heat anyway, and then you have compressed air as a byproduct. Compressed air is not "just" a potential source of on demand power, it's also very low in absolute humidity when it's cooled down and the water has condensed out. At the scale of producing heat for a home, just the fact that the once compressed air has very low water content can have a lot of interesting uses. Also, the heat from water condensation in the frist place improves overall efficiency of heat generation. If the compressed air is used to generate power you can achieve a significant cooling effect, you don't need very high pressures to reach far lower temperatures than required in a freezer. Going with an air compressor to generate the heat, the air can be delivered to a heat exchanger somewhere else, through an insulated line, and then to a tank for storage.
the fact that compressed air does cool down is what makes it inefficient at producing power. back when it was a big thing, they made "reheaters"... kerosene burners in sealed boxes in the airline itself... bring it back up to the temperature it was compressed to, or higher even... when its hot, it wants to expand. when its cold... it wants to contract. its trying to absorb heat, not release it. yes, its a bit of a brain bender ;) if you have a certain volume at a given pressure, and expand it to twice the volume... if it started at ambient, and cools down... the resulting pressure will be less than half... if its hot and cools to ambient as its expanded, it will be at more than half the pressure... and still be capable of performing useful work. once you dispose of the heat of compression, you have to replace it to get that compressed air back to the same conditions it started at. i forget all the terms... isothermic, isobaric, adiabatic... still, they can heat or cool, thats all AC, fridges, and heatpumps are doing... they work fine when the input is constant, they can be tweaked to run at ideal efficiency... that is, they run at a constant speed... the other issue with an air compressor, or wind power in general, is that it takes a certain amount of torque to simply rotate through a cycle. once the turbine can deliver that torque... the compressor cant harness any more power. it always takes the same power to turn over, yet the wind delivers power increasing at the cube of the velocity... twice the speed isnt twice the power, its four times the power! so you need a compressor that ideally can deliver four times as much at twice the RPM. that can vary its delivery rate... not its pressure, its delivery rate... on a cubic ratio to RPM.... can do that really easily with brakes...friction or eddy current types...
@@paradiselost9946 It's the compression part where most power is lost as heat, which when generating heat is the main goal, not a deal breaker exactly. Compressing air should typically generate about as much heat as doing it by friction, but without having to deal with all that friction, and the heat in form of hot compressed air, so no need fro a separate pump. I consider the very small part of the input energy that the cooled down compressed air represents is more a nice and useful bonus, than a great improvement of thermodynamic efficiency of the system. But, it is technically possible to extract around half of that energy as mechanical energy, in a single stage adiabatic expansion, from say 10 bar. Multiple stages with heating in between just from ambient temperature can increase that further. Not easy, but possible, and it has been considered easier to either burn more stuff to generate more power to produce more compressed air, and or burn stuff to add more heat to the compressed air to increase output.
I'm very excited to see how you design and build the drivetrain. Especially if you change speed. My related project is gearing down for more torque and a gear winch is my inexpensive proof of concept. I haven't worked out yet whether a belt or chain from that to the final drive will be most suitable.
I read about an installation, in New York City of all places, that placed a turbine on a building roof and heated water to, as I recall, 168F by stirring. Not bad, all things considered and in the 70s that was probably the most effective way to generate energy that could be easily distributed throughout a building and storing intermittent energy for use later.
Very interesting. Perhaps you could use synthetic oil, steel for the abrasion points, and some round concrete "spacers" in between to apply a bit more force with gravity. You probably would not need too many layers, perhaps 3 or 4, inside a half or full meter by the same vertical sized drum filled with the oil. I suggest synthetic oil because it is inorganic and will not break down and last a long time if you add a mechanical oil filter circuit. Gearing would need to be fairly low, but I bet with a heat exchanger pipe around the perimeter inside the drum you could extract a lot of heat energy. You would probably need some type of a clutch system to get the rotation started, stopped, and create less wear and stress while it gets up to speed. Best wishes for your lovely experiment.
do note that ANY method which results in resistance on the input shaft will result in equal heating with respect to the amount of resistance made, so basically your goal is to, through whatever method possible, produce the highest amount of resistance, and so long as that resistance isnt spent moving energy elsewhere like a generator to power something outside of the box, all the energy put into the system should eventually find its way to heat i think the issue with using metal plates is less so about the wear itself but about the metallic particulates that will accumulate in the medium i think you should consider the baffles idea more strongly, you might be surprised at how much resistance can be made that way. perhaps taking inspiration from the design of torque converters as they have many years of development figuring out how best to make the highest level of friction possible in a fluid coupling, and maybe use a more viscus fluid like oil or even grease, though too viscus would make it difficult to pump through a heat exchanger
I had this same exact idea about a decade ago! I think the best way would be to combine several of the adaptations you mentioned. Use oil instead of water, bearings (made much happier in oil than water), I'd also build the lower bearing up off the floor of the chamber quite a ways because wear particles will inevitably sift downward, although the constant spinning will fling them outwards, away from the center. I'd also use something like car brake pad friction material on alternating surfaces.
A part of me is really irked by the idea of directly turning useful work into much less useful heat. If you want heat from work a much more efficient method would be a heat pump. They move heat instead of creating it, which means you can get three to four times as much heating as the energy you put in. The obvious way to do this would of course be to use an electric generator and to use this to power an electric heat pump, but this would add cost and complexity, not to mention it wouldn't be very efficient. Instead, you could use the air conditioning unit from a car. AC is really the same thing as a heat pump, only in reverse, and most car AC systems are made to be driven directly by the engine. With one of those you could turn your 1kW of rotational energy, into 4 kW of heat, which is certainly enough to make a sizeable difference in your house's heating load.
Technically an induction cooktop is also heat by friction. Pretty easy to implement due to commodity. But this is an interesting experiment! I like the top comment of heating with magnets directly in the fluid, there would be no electrical conversion losses! And no electrics to faff about with of course.
Hi Tim, I'm not the least bit technically competent but two things spring to mind ( one of which you mentioned in passing) metal +water = rust. Also, if you use oil instead, although it solves the rust problem it becomes very prone to catching fire and so quite dangerous. Maybe you expect anyone watching to have more knowledge of engineering than I do, which I admit wouldn't be difficult, but this project seems a bit strange to say the least!
Toyota uses something called a power heater in some vans to use engine power to speed up the heating of the engine coolant in cold weather. It's basically a fluid coupling with the output fixed so it heats the coolant by slipping. No mechanical friction so no wear, just fluid being pumped by a rotating impeller against a stationary turbine wheel. It's driven by the accessory belt and uses an electric clutch similar to the ones used on air conditioning compressors, engaged by a switch in the dashboard. Something similar could probably made from a torque converter but the materials might corrode and bearings seize from lack of lubrication if used with water so an oil to water heat exchanger might be needed.
Once again, tim. It seems you are embarking on a seemingly mad quest, but one that you'll undoubtedly succeed in billiantly, as the mad scientist you are!!! How I would love to come and lend a hand!!!
It would be interesting to run an experiment to see which is more efficient: 1) have the windmill run an electric generator to heat water using heating element 2) the metal plate friction thing. My guess is that if you kept it DC there wouldn’t be a significant difference. Nice thing about using the generator is less moving parts and easier to maintain.
Fantastic, I think the diameter of the discs should be large like a windmill grinding stone, and the amount of liquid as little as possible. If you could achieve tight tolerances the discs may not even have to touch. Thank you!!
Towards the end you mention replacing the water with oil to be run in a primary heat exchanger loop, the problem I see with this is that it (in theory at least) reduces the friction between the plates, but maybe that's not a big problem because the oil is what would be heated instead of the steel. If you increased the pressure of the stack of steel (with springs or more steel plates) it would also produce more heat (at a lower speed but higher torque required). The non contact methods mentioned using magnets would require higher speeds (but less torque), the advantage would be less wear however. In terms of storing the heat, water is pretty good, it holds about 4.2J of heat per gram per degree (one of the best performing substances!), it's a liquid that's easily pumped, it's pretty cheap and it's safe in the event of a leak (at least at low temperatures). It ticks almost every box! Good luck 😊
What if you added holes in the plates and had a rotor and a stator that did not touch other? So the wear would be reduced. And maybe by adjusting the geometry you would also have an inbuilt pump to transport the liquid? Nice projects - keep them coming👍👍. Greetings from Denmark🇩🇰
When I studied mechanical engineering 50 years ago we got the task to design a water heating device driven by a windmill. Our solution was to use a fluid coupling like the truck retarder.
I wonder if you could use brake pads and rotors for something to purchase 'off the shelf' as it were. An old wheel bearing might also work for more parts to use from the car. And I like the idea of the metal bits being in oil, and then a jacket of water running around the outside like a steam boil pot. Only in reverse.
It seems like a great way of filling your heat exchanger with little tiny bits of iron oxide. I think you'd be better off just running a dynamo immersed in water, with the generated current going to resistors in the bottom of the tank, or to power the exchanger pumps.
Very good idea. I imagine the wear while in water will be days to weeks. Oil however may change the wear substantially and that means heat generated will be less, so you would need many more plates or more pressure on the plates. The speed of rotation, I think, will ramp up the heat generated to the second or third power of speed. I presume the windmill will speed up and down with prevailing wind, so perhaps a way of changing the friction depending on speed?
An interesting experiment, to be sure! Some thoughts: 1. Relying on the weight of the discs isn't really a great way to ensure friction. Better would be to have a spring pressing them down. Better yet would be to have that spring compressed by a governor, so that the force exerted on the stack by the spring increases with the RPM of the shaft. That way, when the wind's velocity is low, there won't be much friction from the spring so the shaft will be able to turn easily. As the wind picks up, the spring force--and, thereby, the friction--can increase without stalling the system. 2. To preheat the heat transfer fluid & water, you could first pump them through a compost pile. (Look up 'Jean Pain Compost Heating System' for more info.) 3. Flattening the plates as much as possible beforehand will *DRASTICALLY* increase the amount of surface affected by friction. 4. The fluid currently has a difficult time accessing 90% of the plate surfaces, as they are flat and pressed tightly together. OTOH, if you cut many small radial channels in the spinning plates and cut a larger hole in the center of the slots for more vertical fluid flow, then centripital force will pull the fluid from the center hole through the channels and across the surface of the stationary plates, pulling heat from them as it goes. The fluid will then cycle from the outside to the center to be heated even more. Surrounding the stationary plates with copper water pipes will transfer the heat in the fluid to the water efficiently. 5. As the purpose is to transfer heat to the fluid as quickly as possible, thinner plates should work better, as that increases the amount of surface area per height of stack. 6. As torque seems to be the deciding efficiency factor for this method, the largest stack of plates possible plus a high-torque rotational source--VAWT windmill/paddlemill/etc.--should be the way to go. 7. To remove some of the humidity from your air I suggest you go to the 'Tech Ingredients' channel and watch at least the 'Revolutionary Air Conditioner!' video in the 'Cooling' playlist, as it shows a simple, energy-efficient way to dehumidify (and cool) air. Cheers!
@@wayoutwest-workshopstuff6299 "Thank you Keith - the cnc plasma cutter uses a LOT of air though.." Yeah, you might need to scale up the desiccant system a *LOT* to work with a high-volume air need. ...but that might still be worth it to have as much perfectly dry air as you need for very little power draw.
Here's a cheap option without utilizing copper or magnets. You'll need 2 metal drums that can fit one into another with a gap of about 1" between drums. The outer drum can be a 1/4" steel and it needs a perforated or spread steel sheet lining (about 1/4" thick) welded to it on the inside, with holes about 1/4" in size. The inner drum can be also about 1/4" thick and it also needs to have a perforated steel lining welded on it on the outside. The inner drum is sealed on all sides. So you'll basically will have 2 drums inserted into one another with a "rough surfaces" between them. This is how this heater works: the cavity between these drums is filled with water. You rotate inner drum with a 1hp motor and the rotation will cause cavitations over the perforated steel with holes between the outer and inner drums and you'll get A LOT of steam pretty fast. Cheers from NYC 🎉
Also, this method does not use friction between plates which causes water to look like diarrhea. You don't need an intermediate heat exchanger to isolate dirty water from the house water pipes. You get clean, pure steam. Also, since there's no direct contact with inelastic materials, you don't need instantaneous high torque to start this type of heater.
Regarding the shape of your tower, if the walls were vertical in the area behind the blades and then tapered to the ground, all your shafts and gears could meet at 90 degrees.
While you're experimenting, I think it would be worth trying some of the simpler ideas, like paddles that are less likely to wear. It's likely that they're all nearly 100% efficient. You could use a plug-in power meter to measure how much the drill is pulling from the mains, and calculate the heat capacity of the water to measure the efficiency. Also, if you're only expecting a kilowatt or two, you'll probably need a heat pump to scale that up enough to heat a house.
Tim, copper plates and neodymium magnets on alternating disks. Magneto caloric effect. Heat without friction. No rust, no abrasion.
This! Yeah i like this, i was thinking something with magnets but without it being a motor
Definitely agree! That would be vastly superior. You could get old hard disk magnets, probably fairly cheaply.
expensive
Instead of copper, aluminum, cheaper, also won't rust, and it could also serve as the container. A large aluminum pot for example.
Wouldn't the repeatedly heating up and cooling down of the magnets eventually make them loose their magnetic field strength?
Reading the comments I like the idea of running an air compressor best. You could put the tank under water to get your heated fluid. Then you have free compressed air to get cooling or run other contraptions. Magnetic induction is certainly the most efficient way to heat the water, but I suspect efficiency isn't your only aim with this project!
YOOOO you watch this channel too!?
Thanks, Ben. Luckily lots of smart people watch this channel and I learn a lot from them : - )
Of course you're here 😊👋
Robert Murray Smith has made videos for what is called a friction "frenette"
Where oil is heated between a rotating cylinder and another cylinder
Budget option
@@wayoutwest-workshopstuff6299 If you want to try inductive heating, I think you could affix diametrically magnetized neodymium ring magnets to an aluminum shaft, place this coaxially inside aluminum tubing using stainless steel bearings (to avoid galvanic corrosion due to current flow), and place the whole assembly inside PVC pipe where the water will actually flow. This will keep the mechanism sealed away from the water and the aluminum tubing should work as an optimal shorting ring since the magnet is fully enclosed by it. To maximize the coupling you want the gap between the magnets and the aluminum to be as small as possible. Magnet strength, number of magnets/length of shaft and gap clearance can be adjusted to optimize the load for the drive mechanism. Because the bearings are also in contact with the aluminum pipe, their waste heat should also transfer to the water.
Probably an old torque converter would be ideal. Just stall the output impellor and use the inbuilt pump to circulate oil to your heat exchanger primary circuit.
I agree.
A very similar device that's actually designed to have water as the working fluid and for converting mechanical power into heat is a _water brake dynamometer._
I suggested one of the drums, then realized the whole transmission and tq converter. Fill with water, turn the input, lock the output. Water to water intercooler through the trans cooler lines. Gave ya a thumbs up for getting here first lol
That was going to be my suggestion, they usually have an excess of heat and its already all done for you. You could have multiple and tap off the oil.
Worth a shot, even if the heating is not satisfactory, it could be used as a progressively adjustable brake by varying the fluid level in the converter
The issue with solid on solid friction is that it would wear down leaving particulate in the water and increase the required maintenance. I'm aware that the title is the practicality of it, but it might be more efficient to run a generator to power a heat pump. For even more efficiency you'd need to cut out the electricity and use a mechanically driven compressor but that's even less practical. Just a fun thought.
A compressor is a good idea as an answer to the question of how to convert mechanical energy into thermal energy! When air is compressed, it becomes warm. This compressed air is passed through a long spiral tube surrounded by water. ==> Water gets warm too.
How about the mechanical drive from the windmill to drive the heat pump compressor ?
@@dg0mg Good point I forgot that would happen.
@@stevewilliams2498 That's what I said?
That particulate is why I'd be concerned about this ever being used to heat water for drinking.
Using electricity to do the boiling will likely have a much lower energy loss, if you do the heating beside the house, and transfer the electricity over a distance it should be ok and space shouldn't be as much of an issue.
The earth tends to be a pretty good insulator too, so such a boiler could be next to the house, under a paddock, or pretty much anywhere.
Multiple layers of paddles spinning between paddles that don't spin (stators) cause 'shear' in the water. That creates a lot of heat. Think of an automatic transmission, except with the pitch of the blades and stators being straight.
One fellow here recommended turning a heat pump, and that's an excellent idea.
Yeah a heat pump is ideal here. Could also be an air conditioner in the summer with just a couple extra valves. A car AC compressor as proof of concept and if it works well you can look for a commercial shaft-driven refrigerant pump surplus/craigslist etc.
SHEAR!!!
The absorbers used on water brake dynamometers are simple and have no wearing surfaces. They are designed expressly for converting kinetic energy into heat. Worth investigating I think.
Thank you - I will
@@wayoutwest-workshopstuff6299 ua-cam.com/video/nSNkB0BXnHM/v-deo.html i don't know if you can manufacture something like this in your workshop but the computer voice explains it good and the animation makes sense immediatly!
@@wayoutwest-workshopstuff6299 This is the way. You just need to direct your energy to move the water. Restricting water movement will build you the proper torque to regulate the system to your suitable rpms.
I would try using a submerged pump and recirculating circuit. The same pump can also supply you the water for consumption.
Great Work Earthling
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I freaking love it. Huge progress. Looks so close to being awesome.
Tim, noncontact is probably the way to go. if magnets and induction are too high tech, Then something with viscous fluid being forced through some torturous path.
I also suggest considering a heat pipe to move the heat around. You can make one easily! put a little water or other appropriate fluid in a capped pipe until it boils and then close a valve on the other side to seal the pipe and liquid at low pressure. In use the water boils at low temperature and the steam communicates the heat to the end of the sealed tube. A great pumpless way of moving heat. It’s very very efficient. Of course placing the entire heat generating mechanism in a large tank of water will work also, but the heat pipe is a good trick.
Pumping fluid around needs pumps, and they have friction with the vanes / impeller / whatever, and the liquid. You can't avoid wear.
Heat pipes AFAIK are used mostly in computers where you need to shift a lot of heat quickly in a small space, do there exist great big ones? Since this is for domestic bulk heating, just using chunks of metal, ideally copper, seems better. Heat pipes are for when removing heat is the priority.
Generating electricity to power a heat pump would allow for heat to be extracted both from the air, and also other sources (such as the engines, and furnaces used for processing your wood, and of course the surrounding air, and if practical, under the ground). Friction is certainly an 'interesting option', but I fear that it is rather limited in scope, and rather high in maintenance and consumables - efficiency not really mattering in this case (so I discount it here). Interesting project - which is asking great questions!
I posted another comment about this, but I think a car AC unit is an interesting option. They are designed to use the engine's rotation to power the compressor, which means you wouldn't need an electric generator.
@@MrAwawe Yeah it's probably worth a try. I'm not sure how long you can get a compressor to last, but you definitely need to pay attention to the oil and making sure there's enough, and that it can make it's way home to the pump. You really need to turn them pretty fast to work well, like 1500+ rpm (they are always overdriven by the crank pulley).
I had a similar thought in terms of using a heat pump but think it does not need the complication of converting the energy to electricity to then power the pump(s) and instead they could be direct drive, requires some gearing and either there would need to be a way regulate the stored heat so that if the pump worked continuously it was not a problem or a way to disconnect or regulate the pump once the required temperature is reach which admittedly would be more easily achieved with electrical regulation rather than mechanical.
The VM Motori engine in my car has a viscus heater that takes power from the fan belt and spins a binch of closley stacked plates with a super thick goo between them. Water flows through an isolated channel to absorb the heat. I know it's probably cheating, but it's an off the shelf solution.
in an ICE that just makes no sense when 1/3rd the energy is getting dumped out the cooling system, and the other 1/3rd being dumped out the exhaust pipe...
@paradiselost9946 your not understanding fully.
I'd explain it, but believe it would be a waste of my time as you probably would not comprehend. U pićku materinu, bože pomozite ovim budalama ❤
@@paradiselost9946 True, don't car heaters generally involve heat-exchanging with the radiator heat?
A cavitation pump looks like it’s worth a try. Interesting alternative approach. Thanks for working on it.
His current design isn't too far off from being one other than having plates touch. It just needs holes in the rotor plates as initiation sites for cavitation, correct spacing, and perhaps more RPMs.
I love coming here for these out of the box ideas...things i would never even think of... always something interesting and different love it!
This WAS a great experiment! I don't know anything about friction and heat loss and if it would work. But thats why you're here. I'm sure we're going to find out! That's the super fun part. P.S. Don't get sick, Tim. Thats no fun! 🤪
just wrap copper pipe around your woodstove chimney and insulate it. use the winmill for something else
There was a program in the 80s or 90s called it runs on water. One inventor used a cylinder full of holes strategically placed and rotating to heat water.
This is an interesting experiment and your videos are great! One option might be to couple the mill to a pump and pump the water through small holes rather than small holes moving through water. You could possibly bring the heater to your house with hoses and have minimal loss on the way.
This is one of the most interesting ideas I think you've had in a while. Can't wait to see what you come up with.
If you used oil as a medium to reduce wear, then added a spring to create end pressure. The spring pressure could be adjusted by a flyball governor to regulate the wind shaft speed and ease starting in low winds, cheers
Noise and plate wear are the biggest issues, as well as contamination of the working fluid over time with plate material which would gum up anything you try to pump this into. Still, an interesting experiment!
Very interesting Tim, I had no idea there were so many ways of heating water via mechanical input.
As per other comments my instinct would be to generate lovely useful electricity but suspect that doesn't fit the ethos of the project. After all, that would end up being another wind turbine on a stick, and you've already done that!
Anyway, I like the idea of storing a few tons of warm water, although where you could get it, I don't know: your part of the world has always struck me as being particularly dry ...
All best wishes from East Sussex.
Hi Tim, hope you're okay with your cold and have a speedy recovery! For our plasma cutter we have a twin moisture trap setup. One at the compressor and one at the back of the plasma cutter. It usually works okay whatever the weather.
Thanks - yes, I have those too, plus a refrigerator drier, and it's still not enough sometimes : - (
Perhaps living in Ireland is the problem?!
Just throwing off one-off ideas... A permanent magnet alternator like such in a motorcycle in oil bath with the outputs wired directly through resistors, either in the said oil bath or the adjacent water tank. The stator coils on such an alternator will get pretty damn hot as all the excess energy that's doesn't end up in the resistors as useful electric current would just be dumped into the oil as thermal energy. And if we cooled the oil by exchanging heat with the water tank the total efficiency would be pretty high. No controller needed, no fancy conversions, just three AC outputs from the alternator directly heating the water and if things get too hot and the temperature and the pressure of the water tank would rise enough a safety valve could purge hot water out and a one-way inlet valve could let cold water in to cool down the tank (and thus the alternator oil bath). You could probably find such alternators for pennies from the junk yard and you could scale the unit up by attaching multiple to the same shaft. No physical metal contact besides bearings so the oil would remain clean for a long time.
this is great content, i love messing around and trying to make stuff work
Heat pump ! :)
Direct drive on a compressor from an old fridge : that will be interesting. And you get a cold source at the same time to keep some food.
yeah sounds like a good idea. however a fridge only has a max of 2kw? maybe even only about 200watt. house heating will easily use 10kw. so you would need 50 old fridges.
@@schirmcharmemelone a resistiv electric water heater is 2kW yes.
But a heat pump will use a third of that. A 200 W compressor from a fridge will fit the windmill :)
Fridges are only designed to run for a few minutes a few times per day.
So don't expect that the compressor will survive for long
@@schirmcharmemelone you don't use a domestic fridge. You use a unit from a butchers cold room. These usually have a belt drive from a motor .
100% if you want to be efficient, don't create heat, just move it from somewhere else
I love your "out of the box" ideas... Very creative. Peace man Rolfie
As I’m sure you’re already aware, this is the same method James Joule used to determine the relationship between mechanical power and heat energy. It might be interesting to use this setup to measure how much power your windmill generates?
Thanks you. Good idea. (I wasn't aware - so much to learn!)
Hi Tim. For storing thermal energy at low temperatures, you should look at phase change materials. The energy is locked up in the material as it changes phase from solid to liquid. The energy is released as it changes back from liquid to solid. A good choice for your application might be sodium sulfate decahydrate.
bacon grease has a good solidus to liquidus temperature range (approx 85 to 130F) and can be sealed in mason jars in a holding thank. also you can enjoy a lot of BLTs while you amass the grease.
I too think driving a heat pump would be a great plan. Those things can be 300-400% efficient.
They are a bit of an investment and not easily made at home, I would assume.
@@makingitthrough190 They're basically compressors, which are basically pumps. You could knock something up at home, and even if it's not optimal, just having a heat pump at all makes it easy to be super-efficient. Getting a professional system is an option and then you'd be able to use it on normal mains electricity as well, the DIY system would also have to supply electricity to it. If you're making it cheaply out of scrap, though, it seems like as good a use of your time as any. You'd put a loop of piping down in the ground, or else just use air-sourced to start with. Then once it's installed, you leave that, and only tinker with the moving parts indoors and above-ground.
Cool experiment. But I’m really enjoying the comment section. Some really great ideas. One that I found partially interesting was having a copper coil with water running through. Fire is often the way to go with this method but maybe friction or magnets in this scenario might work. Also, fire could work but use the windmill to pump air into the fire, like a forge, to super heat the fire, and heating the water much faster. More of a hot water on demand situation. Also really like the compressor idea, where you could go with a heat pump type situation. Great stuff! Look forward to seeing where you go with this. Keep experimenting!
I have always loved the idea of using a windmill to get heat through friction. In theory the efficiency can be really high. The heat can be easily stored for some period of time.
It's a challenge to match speeds and forces though, and variablitity would be great.
In your setup, I'm pretty sure you can get heat through fluid friction alone without the plates wearing. Couldn't you make an inefficient pump forcing fluid through cntrollable contraints? Anyway, I'm guessing water-brakes are a pretty well-established industrie.
I'm happy to be sponsoring this project.
High speed blenders cook soups using the same physics but the friction is made by moulding ribs in the wall of the 'paint can'. Of course this would cause wear in the holding vessel which couldn't easily be replaced. I wonder if you can just have a spinning shaft creating a vortex in a smooth vessel - but have vertical rebar rods staggered throughout to create the friction. When they get consumed then it would be easier to replace with off the shelf parts than having to fabricate new plates. Would probably be trading efficiency for convenience though
When making aluminum ships, sometimes the seams are 'friction stir welded'. We went to the navy shipyard to see it being done when I worked at the shipyard. Did you factor-in the cost of the steel? How fast would the steel wear away and need to be replaced? 🤔 How about driving a heap pump to cool and heat?
Hi Tim, how about now trying to power a heating element with an old car alternator driven by the drill, measure the energy required to power the drill to raise a fixed amount of water by a fixed amount. Then compare to the friction method. Then you will have reliable data on which is more efficient 👍 great vids, keep them coming!
I was thinking the same thing. It would be interesting to know whether the friction method is more or less efficient than the electric method. I think the electric method would have more benefits though - no mechanical link needed between the windmill and the heater, minimal wearing of parts, ability to heat water directly without heating oil and using a heat exchanger, ability to use alternate energy sources other than wind, and so on. The only drawback would perhaps be the cost of the generator/alternator, but then you'd need less plasma cut metal plate so maybe it would work out much the same?
Theoretically, the friction method is more efficient because all of the energy is converted to heat.
With an alternator, the alternator is going to lose efficiency due to friction and that can't be submerged as easily, reliably and cheaply as just some friction plates to be able to sink the alternator heat back into the system as useful heat.
The nice thing about the friction method though is that 100% of the energy put into the system is put into heating the fluid.
Then it just becomes a question of if the fluid can handle more heat, if your insulation can retain it, or if you can actually make use of it with whatever the secondary system is.
But all of those variables would remain the same no matter what method he uses.
@@doggfite Some good points there. Alternator friction would surely just be in it's bearings, the friction method in the video would need bearings in the final design too. Thinking of the bigger picture my idea was that there will also be a fair bit of energy lost in any angle drive at the top of the windmill whereas an alternator could be mounted up there meaning no need for those losses, just minor losses in the electrical transmission. Braking system is another story!
@@doggfite You'd need a bearing up on the windmill blade though which would be the same whether you're electric or friction. After that you might get a small amount of air resistance on the friction shaft and likely a lot of noise which both reduce the amount of energy that can be converted to heat, and which are both not losses in the electric version. I really think it would be a pretty close call.
direct heating with friction... all the energy contributes to heating.
using an alternator... the amount of energy appearing in the resistive load is a ratio between the load and the generator resistance. at best, you get 50% of the applied power into the resistor, when the resistances are equal. the generator will absorb the other 50%. yes, the turbine will deliver twice the power as what you read in the load resistor...
if you just short the generator, all the energy appears as heat in its windings. the current will be limited by the wire sizes and magnetic fields...
if the load is higher in resistance, more heat appears in the resistor than the windings, but you cant "push" as much power through that resistor, that circuit, anymore, as the current is limited... you deliver less power overall.
so rewind an alternator with 3/16 copper pipe, shorting each phase to itself... no worry about star or delta... and tickle the field windings with a voltage appropriate to wind speed (tip speed ratio, actually...) so as to apply a load that is directly proportional to the energy in the wind.
which increases on the cube of the velocity.
yes, that needs an external power supply.
easier to make a retarder... permanent magnets, conductive disc, variable airgap. use a centrifugal governor to control the airgap and the braking force... conductor gets stinking hot. add coolant...
you need a load that increases as the wind picks up. pumps, generators, whatever... they all have a fixed amount of power required to simply do what they do. a wind mill takes so much to grind grain, to lift a plunger full of water on every revolution, to deliver so many amps at so many watts into a load... and thats it. they do it faster, it takes the same amount of power to do what they do. yet as they speed up, the wind applies more power, produces more torque... so we have to feather the blades or apply brakes! rather than USE it, we LET IT SLIP PAST.
and to make grid-connectable AC voltage at 50/60 hz from the wind directly? HA! that simply doesnt work. at all.
if all you do is make heat, you can "hold the brake on" harder, and that just makes more heat! can limit blade speeds, stay in the peak of their efficiency curves...
the temperature reached is a matter of how many watts are delivered and how many are dissipated in any given volume... obviously as wind speed picks up things get hotter... much hotter!
what can you do with hot water?
hmmmmmm.... steam turbines?
hot showers?
i need a shower... pong.
This is a great idea because heating water with a windmill using electricity will lose ~ 70% of the energy heating the generator. For your application you want to turn 100% of the power from the windmill into heat, and the power of the windmill will vary widely over the course of time. I think you want a friction brake like a disc brake or a drum brake and then have a governor apply enough brake to keep the windmill turning at a reasonable speed. If you use a weighted brake the brake force will be the same when the wind is blowing lightly or very hard - you'll get nothing when the wind is light and you'll miss a bunch of energy when the wind is strong.
This kind of heater exists in mass production in cars, its called a viscous heater, used in some mercedes cars, its filled with a high viscosity oil heated by spinning plates, in order to preheat the coolant in a diesel engine on a cold day and bring cabin heat on faster. Could be inspiration for a more efficient design! Cheers
Thanks - I'll investigate..
Is this modern or ancient Mercedes tech. Mercedes diesel... 80's then?
I have nothing to add but wow! I can't wait to see this windmill!
At the start I was like this is madness, at the end was like this has potential. Makes sense, a large magnet could trap the steel particles in one place for removal as the plates wear out.
Hello Tim, they still make oil impregnated wooden bearings for use in sewer plants and other under water applications.
Something that could come in handy, cheers.
and I still use them for my railway wagons
Depending on what you want the water for, it may be worth making a heat exchanger, where you've got water in pipes, and water in the heater, but they don't actually mix. This would make it easier to swap out the heating element as needed, and prevent the risk of additional contamination
Magnetic induction heater would be a better converter of rotation to heat.
why would it be better though? They both work, but one would cost a lot more than the other, surely?
@@wayoutwest-workshopstuff6299 way less maintenance. no wear. you can make anything a magnet with an electronic magnet, all you need is a copper coil and some DC electricity. just imagine the rust water you will generate. and then the iron is in water all the time. i watched all your videos in the span of a few weeks and saw all your projects rust away after a few winter. insane how rusty stuff becomes in your area so close to the sea!
Another alternative would be to use break disks. They are designed for this task. But if you ever looked at the wheels of a used car all that dark brown dust is the old break disk turned into a powder! do we really want to fine grind so much metal into dust?
From the amount of comments suggesting magnet heater. you surely can ask some high performance nerd from the comments to calculate all the hard stuff for you :P you just need to ask in a video nicely :P
@@schirmcharmemelone He said in the video he was planning to fill the container with oil so as to avoid the rust, and use a heat exchanger to transfer the heat across to clean water
@@wayoutwest-workshopstuff6299 you would not need to use a heat exchanger. Just a spinning plate of magnets and a metal plate in the tank. No plates rubbing and deteriorating in the water.
@@Berkeloid0The problem isn't rust, but the basic steel against steel friction that will occur. It's an interesting experiment but those plates would be larger, more expensive, and the forces between them much greater in the actual machine.
Interesting experiment! I was genuinely surprised to see that it actually produced such promising results. I wonder if ceramic plates would work even better? Thanks for sharing.
Something to also consider: windmills can self-destruct in high winds due to excessive rotational speed. If your churn-gadget is equipped with a mechanical pump whose pumping capacity scales with rotational speed then as the windspeed increases so does the pump which fills the churn with deeper and deeper water. Your paddles/disks will need to have an air gap (the hard part) so that when in air there is minimal heating, but as the water level rises more and more paddles are covered with water and begin producing heat. All that energy dissipation adds to the resistance to turning which in turn moderates the windmill keeping it from self destructing. A Nice feedback loop. A dual viscocity oil would seem to also be a very good option as the shear increases so does the viscocity and power generating potential.
BTW, a neighbour had come up with a very similar idea as this about 40 years ago, but as far as I know never implemented it.
I do like your "well, let's give it a try" attitude!
Why not use air compression as a source of heat. Notice how hot a plastic bicycle pump gets when inflating a tyre. Use a few immersed in a water tank by way of heat exchange and connected by a crank. Any air produced can pressurise the water tank (obviously with a relief valve) to provide a pressured warm/hot water supply without the need for an extra water pump.
if you can find a local engineering company with a surface grinder they could stick your plates up and grind them perfectly flat and smooth. oil would definitely be good. really interesting project, following!
there was a device a few years ago that used cavitation. the collapsing "bubbles" produce the heat. It used a drum with dimples in the outside surface.
Hey Tim i saw an interesting idea to do the same thing.
A rotor with dimples offset in a tube.
This was all under water
As it spun it created cavitation in the dimples as it went from low pressure to high pressure
Huge rpm though?
Brilliant! Once enough friction occurs, you may have metal particles in your hot water. How about some sort of heat exchanger to keep the metal separated from the water?
Hello Tim, good questions you are asking. If it were run in a oil, that could help smear it and have less wear maybe. In water and if not much air got to the plates, that also could be somewhat better?
Like how you go about with your projects, always nice to see various methods from the regular viewpoints.
Thanks and cheers 👍💪✌
Every windmill has a certain ratio of windspeed to rpm where it is most efficent. That means that if you want maximum power you would always have to adjust the rpm to the current windspeed. The good thing about a load like a paddle where the torque that the water created is proportional to the rpm squared is that it controls the rpm by itself that it follows the points of maximum efficiency of the windmill by itself. As long as you just set the gearing and paddle sizes optimal for one windspeed, it will be optimal for other windspeeds too. Hope that was understandable
I like this idea as a direct way to generate heat directly via the rotation of the windmill, but I feel like there's a few issues that could make it unfeasible on a small scale.
Corrosion - if you have mild steel plates in a heated, wet, environment would they rust very quickly? And if so, what effects would all that rust particulate have on the system? Especially if you plan to pump the water into radiators.
Stainless plates might solve this issue but I imagine they'd be prohibitively expensive.
Wear - with a mild steel plate I don't think they'd last long before they'd begin to wear, especially if they're heated and going rusty. You'd then need to constantly adjust the pressure on the plates as they wear thinner to maintain friction as the plates reduce in size. This wear generates more particulates as well.
Torque - if you scale up the heater large enough to heat the body of water required to heat a house, Will the windmill have sufficient torque to drive the bigger heater? I'm assuming larger plates would increase the necessary torque exponentially. If you switched to an oil system rather than water, it would solve the rust issue, and aid in reducing wear, but the oil is more viscous. More viscous oil could further increase the torque required to spin those plates, again increasing demand on your windmill.
Demand - if the windmill isn't spinning fast during a time of peak demand for heat, then there's suddenly no heat. Is the wind in winter enough to rely on for heating?
I think a water brake system with paddles seems easier to build and maintain, as well as more easily scaleable to the size necessary to heat a house.
I know it doesn't fit so well with the ethos of your project but turning an electric generator instead of all those ideas seems more efficient, and far easier to build/maintain.
Friction vs. Shear Force - I've had a car with an auxiliary water heater powered by the drive shaft - it was said to use shear forces in liquid to generate heat. It would be interesting to see if you could generate the same amount of heat as before even without the plates touching if you cut elongated slits into both rotor and stator plates. That way you could minimize wear & tear on the plates.
Perhaps a sand battery would be your cup of tea? You should be able to heat sand with friction too, and you could just run some length of copper (water)tubing through your sand battery to create a heat exchanger.
This is a very clever idea, but I can immediately see some problems with it:
1. having metal-on-metal contact with the explicit purpose of friction is going to chew away the plates. This will
2. fill the liquid with metal particles, necessitating regular replacement of that liquid. (I am glad you mentioned using a liquid-to-liquid exchanger; this stuff would not be good to drink.) You're still going to have to add a filter before the exchanger, thought, lest you fill it full of rust.
3. The warmer you run the water, the more of a wearing issue you're going to have; the higher the temps, the easier it is for steel to rust when in contact with water. This makes me think using an oil would be a better choice. (I don't know how using an oil would change the ability to generate heat though.)
4. I'd be interested to see if the heat generation keeps up over a longer period; as the plates wear, they should 'bed' into each other, reducing the amount of friction generated to some degree after the 'break-in' period.
My gut says that one of the designs you showed earlier int he video would be a better way to go about it; while direct contact would heat the fastest, it will have a number of maintenance concerns. Still, I wish you luck!
you could be right, but I suspect there would be no rust after a couple of days because all the oxygenn in the water will have been used up
@wayoutwest-workshopstuff6299 not sure it will. You'll probably need an additive package of corrosion inhibitors. Tried this on a machine at work last year...it's surprising how churning water in system with a low open area picks up oxygen very quickly.
I changed to 50% glycol.
Running a centrifugal water pump with the circulation through a small venturi will heat the water, and the small venturi will stop the ceramic bearings from overheating.
You will now have a pressurized holding tank and pressure will reticulate your water, also now you will have a low pressure feed line into the pump to supply the whole system.
Many years ago, a farmer in the US made a shed with pieces of Fresnel lens, from an old lighthouse, in the roof directed at a drum of water. Even in moderate light this would boil water for a steam generator. He ran a large farm off of electricity/batteries. He used early batteries that were practically indestructible.
Hi Michael, I'd love to read more about this farmer but I couldn't find anything online. Can you point me in the right direction?
Hi Tim, what a nice experiment!! I have go off at a good start. Love to follow your path with the windmill construction to create energy to heat your house. Comming from holland windmills have always been of intrest to me 😊
Hi Tim, I have an idea. You could use thinner plates, they would still be strong enough, but you'd have more surface area of friction in the same space occupied by the bigger plates. I think you get what I'm saying.
I think the paint in the water could affect the friction.
Brilliant experiment btw
The particulate sludge/slurry that would build up would become a problem fairly quickly, I think, and would itself speed up the degradation of the disks. It would be worth seeing how much thinner the disks had become during your testing to estimate how long they would last, and/or you could test the specific density of the water to figure out how much steel was getting into it. I would echo the other people in the comments saying that a heat pump might be the best thing to power with your windmill, although I appreciate that it's not a cheap DIY solution unless you want to try to build one yourself!
Now, if only my high school physics classes had had an approach like this…..
Quite a long time ago, there was a company trying to get investment in a 'revolutionary' water heater - it consisted of a solid metal cylinder on an axial spindle. The curved surface of the cylinder was drilled with many shallow cavities and the whole thing was enclosed in a reasonably close fitting cylindrical jacket.
Water was passed through the apparatus as an electric motor spun the cylindrical rotor at high speed.
It heated water quite effectively, supposedly some pressure effect of the cavities all over the surface of the rotor.
The inventor was claiming that it generated more heat than could be generated by the electrical power consumed, which is instantly suspicious, as this device did not seem to be any kind of heat pump.
I don't know what became of it. Maybe the whole thing was a scam.
It was a scam
I was pleasantly surprised at the amount of heat it generated. But do those plates actually have to physically rub against one another ? - I'm thinking - supporting the "stator" plates at their edges, and the "rotor" plates being supported in between the stators by washers or short pieces of metal tube on the shaft, preventing any of the plates from touching one another. You might be able to have the plates in close proximity without touching with perhaps just a few mm of water-filled spacing between the moving and non-moving elements if you can get the plates and spacers snug enough so there's not too much play in them.
Very, very clever, well done
Very interesting, i was quite impressed by how quick the water warms up. I think you would probably have to have an indirect system whereby this heated water would be pumbed through a pipe through the main cylinder of water. Thus you would avoid contamination from metal filings from the friction. I know this would complicate things somewhat.
I wonder if using different metals would make any difference to the process?
Well done Tim - interesting experiment. I think that the one major problem is the wear factor on the plates - are there other materials that culd be used to overcome this?
for the kettle crowd.
using a generator to run a heat pump is a more efficient way to heat water.
you can move 3-4 times the heat that resistive element creates.
Some years ago I saw a system where a horizontal cylinder had rows and rows of divots drilled into it spaced fairly close together. This was contained inside a steel drum that had lots of divots drilled on the inside, facing the cylinder. They were both within a few millimeters of each other. The cylinder was spun at speed inside the drum with water in between. Something to do with cavitation I think. It was extremely efficient and produced huge amounts of very hot water. The divots looked like about 25mm and 10mm deep.
Maybe dig a hole & put your friction heater in, soil acting as a low cost insulator for heat & sound, top up water as needed via surface tank using a level indicator, & extract via a heat exchanger. As you don’t need high temperatures for central heating water would be fine & also as it’s normally windy where you are you can get away without storage. Probably after a while you will ignore the noise of the wind mill & it would be off for about six months during summer when you don’t want house heating, although you could kiln dry wood or do other jobs with the heat when not needed to heat the house. Thanks for sharing!
Dig a big hole. fill it with insulating layer of styrofoam etc. then a big layer of sand to keep heat. then the water tank with the friction heater inside.
Ok I'll admit that I have never really thought of this. But, I do have a couple of ideas. Such as using a sand battery for storage maybe ? Each climate things work differently with. Here in Arizona USA it is a very dry climate where there in Ireland is definitely a wet climate. We do have a winter not much of one but, it does get cold at night especially. We do get a couple of snow storms but, nearly no build up of snow. We have had snow but, it never stays for more than a day but, that still doesn't mean we don't get cold and night time temps are rather cold. I've knocked around the used oil stove idea because we do have a fireplace and, I'm attached to my walker these days so collecting wood is not going to happen. Being young and unable has some disadvantages you know. Anyway I'm curious how long the metal plates would last but, I like the idea of using oil in it. Keep working on it and I'll keep watching. My projects are trying to build a wind generator for my friends cabins he's getting ready to build. I like the idea of a versicle windmill because it seems that it would be a better for where i'm at. Good luck ahead I love your channel !
That's quite significant heating for something you made it look like you more or less "throw together" in the video. I do agree with other comments that induction would have a big advantage for long term use, but obviously that would require a lot of magnets, that can handle the temperature, some magnets starts to loose their magnetism at temperatures well below 100 °C, and if the system happens to run dry for any reason 100 °C is no longer the limit.
Personally I'd might go with a belt driven air compressor to generate heat. The vast majority of the power a common air compressor uses turns into heat anyway, and then you have compressed air as a byproduct. Compressed air is not "just" a potential source of on demand power, it's also very low in absolute humidity when it's cooled down and the water has condensed out. At the scale of producing heat for a home, just the fact that the once compressed air has very low water content can have a lot of interesting uses. Also, the heat from water condensation in the frist place improves overall efficiency of heat generation.
If the compressed air is used to generate power you can achieve a significant cooling effect, you don't need very high pressures to reach far lower temperatures than required in a freezer.
Going with an air compressor to generate the heat, the air can be delivered to a heat exchanger somewhere else, through an insulated line, and then to a tank for storage.
Oh man! More things to think about : - )
the fact that compressed air does cool down is what makes it inefficient at producing power.
back when it was a big thing, they made "reheaters"... kerosene burners in sealed boxes in the airline itself... bring it back up to the temperature it was compressed to, or higher even...
when its hot, it wants to expand. when its cold... it wants to contract. its trying to absorb heat, not release it. yes, its a bit of a brain bender ;)
if you have a certain volume at a given pressure, and expand it to twice the volume... if it started at ambient, and cools down... the resulting pressure will be less than half... if its hot and cools to ambient as its expanded, it will be at more than half the pressure... and still be capable of performing useful work.
once you dispose of the heat of compression, you have to replace it to get that compressed air back to the same conditions it started at.
i forget all the terms... isothermic, isobaric, adiabatic...
still, they can heat or cool, thats all AC, fridges, and heatpumps are doing... they work fine when the input is constant, they can be tweaked to run at ideal efficiency... that is, they run at a constant speed...
the other issue with an air compressor, or wind power in general, is that it takes a certain amount of torque to simply rotate through a cycle. once the turbine can deliver that torque... the compressor cant harness any more power. it always takes the same power to turn over, yet the wind delivers power increasing at the cube of the velocity... twice the speed isnt twice the power, its four times the power! so you need a compressor that ideally can deliver four times as much at twice the RPM. that can vary its delivery rate... not its pressure, its delivery rate... on a cubic ratio to RPM....
can do that really easily with brakes...friction or eddy current types...
@@paradiselost9946 It's the compression part where most power is lost as heat, which when generating heat is the main goal, not a deal breaker exactly.
Compressing air should typically generate about as much heat as doing it by friction, but without having to deal with all that friction, and the heat in form of hot compressed air, so no need fro a separate pump.
I consider the very small part of the input energy that the cooled down compressed air represents is more a nice and useful bonus, than a great improvement of thermodynamic efficiency of the system.
But, it is technically possible to extract around half of that energy as mechanical energy, in a single stage adiabatic expansion, from say 10 bar. Multiple stages with heating in between just from ambient temperature can increase that further. Not easy, but possible, and it has been considered easier to either burn more stuff to generate more power to produce more compressed air, and or burn stuff to add more heat to the compressed air to increase output.
I'm very excited to see how you design and build the drivetrain. Especially if you change speed. My related project is gearing down for more torque and a gear winch is my inexpensive proof of concept. I haven't worked out yet whether a belt or chain from that to the final drive will be most suitable.
I read about an installation, in New York City of all places, that placed a turbine on a building roof and heated water to, as I recall, 168F by stirring. Not bad, all things considered and in the 70s that was probably the most effective way to generate energy that could be easily distributed throughout a building and storing intermittent energy for use later.
Very interesting. Perhaps you could use synthetic oil, steel for the abrasion points, and some round concrete "spacers" in between to apply a bit more force with gravity. You probably would not need too many layers, perhaps 3 or 4, inside a half or full meter by the same vertical sized drum filled with the oil. I suggest synthetic oil because it is inorganic and will not break down and last a long time if you add a mechanical oil filter circuit. Gearing would need to be fairly low, but I bet with a heat exchanger pipe around the perimeter inside the drum you could extract a lot of heat energy. You would probably need some type of a clutch system to get the rotation started, stopped, and create less wear and stress while it gets up to speed. Best wishes for your lovely experiment.
I love your videos, they are fun to watch and listen to!
do note that ANY method which results in resistance on the input shaft will result in equal heating with respect to the amount of resistance made, so basically your goal is to, through whatever method possible, produce the highest amount of resistance, and so long as that resistance isnt spent moving energy elsewhere like a generator to power something outside of the box, all the energy put into the system should eventually find its way to heat
i think the issue with using metal plates is less so about the wear itself but about the metallic particulates that will accumulate in the medium
i think you should consider the baffles idea more strongly, you might be surprised at how much resistance can be made that way. perhaps taking inspiration from the design of torque converters as they have many years of development figuring out how best to make the highest level of friction possible in a fluid coupling, and maybe use a more viscus fluid like oil or even grease, though too viscus would make it difficult to pump through a heat exchanger
you could try adding magnets or heavy weights to help compress the plates more, might be worth a go.
great way to create really clean metal fragments.
I had this same exact idea about a decade ago! I think the best way would be to combine several of the adaptations you mentioned. Use oil instead of water, bearings (made much happier in oil than water), I'd also build the lower bearing up off the floor of the chamber quite a ways because wear particles will inevitably sift downward, although the constant spinning will fling them outwards, away from the center. I'd also use something like car brake pad friction material on alternating surfaces.
A part of me is really irked by the idea of directly turning useful work into much less useful heat. If you want heat from work a much more efficient method would be a heat pump. They move heat instead of creating it, which means you can get three to four times as much heating as the energy you put in. The obvious way to do this would of course be to use an electric generator and to use this to power an electric heat pump, but this would add cost and complexity, not to mention it wouldn't be very efficient. Instead, you could use the air conditioning unit from a car. AC is really the same thing as a heat pump, only in reverse, and most car AC systems are made to be driven directly by the engine. With one of those you could turn your 1kW of rotational energy, into 4 kW of heat, which is certainly enough to make a sizeable difference in your house's heating load.
Technically an induction cooktop is also heat by friction. Pretty easy to implement due to commodity. But this is an interesting experiment!
I like the top comment of heating with magnets directly in the fluid, there would be no electrical conversion losses! And no electrics to faff about with of course.
Hi Tim, I'm not the least bit technically competent but two things spring to mind ( one of which you mentioned in passing) metal +water = rust. Also, if you use oil instead, although it solves the rust problem it becomes very prone to catching fire and so quite dangerous. Maybe you expect anyone watching to have more knowledge of engineering than I do, which I admit wouldn't be difficult, but this project seems a bit strange to say the least!
Thanks Abigail - I'm just working on another to try to make it clearer
Toyota uses something called a power heater in some vans to use engine power to speed up the heating of the engine coolant in cold weather. It's basically a fluid coupling with the output fixed so it heats the coolant by slipping. No mechanical friction so no wear, just fluid being pumped by a rotating impeller against a stationary turbine wheel. It's driven by the accessory belt and uses an electric clutch similar to the ones used on air conditioning compressors, engaged by a switch in the dashboard. Something similar could probably made from a torque converter but the materials might corrode and bearings seize from lack of lubrication if used with water so an oil to water heat exchanger might be needed.
Once again, tim. It seems you are embarking on a seemingly mad quest, but one that you'll undoubtedly succeed in billiantly, as the mad scientist you are!!! How I would love to come and lend a hand!!!
Water brake engine dynamometer is basicly a water heater.
It would be interesting to run an experiment to see which is more efficient: 1) have the windmill run an electric generator to heat water using heating element 2) the metal plate friction thing.
My guess is that if you kept it DC there wouldn’t be a significant difference. Nice thing about using the generator is less moving parts and easier to maintain.
Fantastic, I think the diameter of the discs should be large like a windmill grinding stone, and the amount of liquid as little as possible. If you could achieve tight tolerances the discs may not even have to touch. Thank you!!
Towards the end you mention replacing the water with oil to be run in a primary heat exchanger loop, the problem I see with this is that it (in theory at least) reduces the friction between the plates, but maybe that's not a big problem because the oil is what would be heated instead of the steel.
If you increased the pressure of the stack of steel (with springs or more steel plates) it would also produce more heat (at a lower speed but higher torque required).
The non contact methods mentioned using magnets would require higher speeds (but less torque), the advantage would be less wear however.
In terms of storing the heat, water is pretty good, it holds about 4.2J of heat per gram per degree (one of the best performing substances!), it's a liquid that's easily pumped, it's pretty cheap and it's safe in the event of a leak (at least at low temperatures). It ticks almost every box!
Good luck 😊
What if you added holes in the plates and had a rotor and a stator that did not touch other? So the wear would be reduced.
And maybe by adjusting the geometry you would also have an inbuilt pump to transport the liquid?
Nice projects - keep them coming👍👍. Greetings from Denmark🇩🇰
When I studied mechanical engineering 50 years ago we got the task to design a water heating device driven by a windmill. Our solution was to use a fluid coupling like the truck retarder.
But I imagine you had much higher rpm?
I wonder if you could use brake pads and rotors for something to purchase 'off the shelf' as it were. An old wheel bearing might also work for more parts to use from the car. And I like the idea of the metal bits being in oil, and then a jacket of water running around the outside like a steam boil pot. Only in reverse.
It seems like a great way of filling your heat exchanger with little tiny bits of iron oxide. I think you'd be better off just running a dynamo immersed in water, with the generated current going to resistors in the bottom of the tank, or to power the exchanger pumps.
Tim, you might investigate the use of more viscous fluids, like resins, custard or... red paint!
Very good idea. I imagine the wear while in water will be days to weeks. Oil however may change the wear substantially and that means heat generated will be less, so you would need many more plates or more pressure on the plates.
The speed of rotation, I think, will ramp up the heat generated to the second or third power of speed. I presume the windmill will speed up and down with prevailing wind, so perhaps a way of changing the friction depending on speed?
Well done! I would have over thought that right of the git-go. And elegant proof of concept with whatevers clever.
An interesting experiment, to be sure! Some thoughts:
1. Relying on the weight of the discs isn't really a great way to ensure friction. Better would be to have a spring pressing them down. Better yet would be to have that spring compressed by a governor, so that the force exerted on the stack by the spring increases with the RPM of the shaft. That way, when the wind's velocity is low, there won't be much friction from the spring so the shaft will be able to turn easily. As the wind picks up, the spring force--and, thereby, the friction--can increase without stalling the system.
2. To preheat the heat transfer fluid & water, you could first pump them through a compost pile. (Look up 'Jean Pain Compost Heating System' for more info.)
3. Flattening the plates as much as possible beforehand will *DRASTICALLY* increase the amount of surface affected by friction.
4. The fluid currently has a difficult time accessing 90% of the plate surfaces, as they are flat and pressed tightly together. OTOH, if you cut many small radial channels in the spinning plates and cut a larger hole in the center of the slots for more vertical fluid flow, then centripital force will pull the fluid from the center hole through the channels and across the surface of the stationary plates, pulling heat from them as it goes. The fluid will then cycle from the outside to the center to be heated even more. Surrounding the stationary plates with copper water pipes will transfer the heat in the fluid to the water efficiently.
5. As the purpose is to transfer heat to the fluid as quickly as possible, thinner plates should work better, as that increases the amount of surface area per height of stack.
6. As torque seems to be the deciding efficiency factor for this method, the largest stack of plates possible plus a high-torque rotational source--VAWT windmill/paddlemill/etc.--should be the way to go.
7. To remove some of the humidity from your air I suggest you go to the 'Tech Ingredients' channel and watch at least the 'Revolutionary Air Conditioner!' video in the 'Cooling' playlist, as it shows a simple, energy-efficient way to dehumidify (and cool) air.
Cheers!
Thank you Keith - the cnc plasma cutter uses a LOT of air though..
@@wayoutwest-workshopstuff6299 "Thank you Keith - the cnc plasma cutter uses a LOT of air though.."
Yeah, you might need to scale up the desiccant system a *LOT* to work with a high-volume air need. ...but that might still be worth it to have as much perfectly dry air as you need for very little power draw.
Here's a cheap option without utilizing copper or magnets. You'll need 2 metal drums that can fit one into another with a gap of about 1" between drums. The outer drum can be a 1/4" steel and it needs a perforated or spread steel sheet lining (about 1/4" thick) welded to it on the inside, with holes about 1/4" in size. The inner drum can be also about 1/4" thick and it also needs to have a perforated steel lining welded on it on the outside. The inner drum is sealed on all sides. So you'll basically will have 2 drums inserted into one another with a "rough surfaces" between them. This is how this heater works: the cavity between these drums is filled with water. You rotate inner drum with a 1hp motor and the rotation will cause cavitations over the perforated steel with holes between the outer and inner drums and you'll get A LOT of steam pretty fast.
Cheers from NYC 🎉
Also, this method does not use friction between plates which causes water to look like diarrhea. You don't need an intermediate heat exchanger to isolate dirty water from the house water pipes. You get clean, pure steam.
Also, since there's no direct contact with inelastic materials, you don't need instantaneous high torque to start this type of heater.
I think this could work too - thanks. But I guess it would need higher speeds. I'll have a think...
Regarding the shape of your tower, if the walls were vertical in the area behind the blades and then tapered to the ground, all your shafts and gears could meet at 90 degrees.
While you're experimenting, I think it would be worth trying some of the simpler ideas, like paddles that are less likely to wear. It's likely that they're all nearly 100% efficient. You could use a plug-in power meter to measure how much the drill is pulling from the mains, and calculate the heat capacity of the water to measure the efficiency.
Also, if you're only expecting a kilowatt or two, you'll probably need a heat pump to scale that up enough to heat a house.
Very interesting. Thanks Tim 😊