Issues to correct if you want to use this in a plane: 1. It weighs too much. Make it thinner, eliminate all of those bolts. 2. The shaft bearing is too large and bulky. Do you even need it? The rotor is made of Teflon which has low friction so maybe it can act directly as a bushing. Might help with sealing too. 3. Maybe go back to a 3 vane design now that you've changed the mechanism. 4. Experiment with different geometries for the exhaust port to exhaust faster and reduce back pressure. The vane is on an angle, so the exhaust port can match that angle across the whole vane length to the rotor along the swept area.
Check out the type of air seals used in jet engines. labyrinth seals. Also I forget what they are called. But there's little indented rings around mortar shells. Those help trap the gas without any friction with turbulence. Of course both jets and mortars have a lot of gas so leaks are less of a worry than people think. But there might be something worth stealing because they are both incredibly low friction.
Integza, about 23 years ago as my thesis project for Mechanical Engineering Technology, my friend and I designed a 4-bar mechanism that solved this problem. We called it the QRP or Quick Return Piston, because it had a 270 degree downstroke and a 90 degree upstroke. I still have the files and paper if you are interested.
Simply fantastic work! The pressure regulator acts like a restriction in the feeding line. The pressure drop is wasted energy (deltaP X Flow). You can compensate the pressure variation (and, thus, torque) changing the excentricity of the engine Higher the excentricity, higher the torque for the same air pressure. Note that, initially, when you have higher pressure,you will need a smaller excentricity to generate the needed torque. Lower excentricity leads to lower flow, thus reducing compressed air consumption. When the air pressure is low, at the end, the excentricity is increased, sustaining the needed torque for longer. This can be achieved with a movable engine housing, actuated by the inlet pressure Look for "variable displacement vane pump" Greetings from Brazil
So here we go. 1. With only 2 vanes, the engine is pulsing. 3 or 4 would increase the surface area to catch the air. 2. The ball bearing is overkill, make the case tight around the shaft. Experiment with o rings or a ledge. 3. If you're regulating the pressure to 2 bar, then you can reduce the thickness and weight of the housing. 4. Instead of vanes, you could use disks. Alot like a tesla engine just small enough to save weight. 5. Rotating mass will be your friend for extended run times due to the light weight. Attaching the propeller with a larger single bolt will help the fluctuation in rotational speed. 6. Inceasing the size of the exhaust port would allow the air to easily escape, increasing the pressure difference on the inlet which would increasing torque. All in all, a really interesting build and your build process is really relatable. Keep this series up until you battle Tom for air superiority!
@@-danR The inlet Port should be putt more into an angel. Maybe 10° more degree towards the roation and three flaps. So the Air pressure is directed to the Flaps instead of "filling" the room.
Several improvements are possible: 1. Drop huge 2 psi valve and resort to using a 3D printed reed valve integrated directly in the motor. Why? Weight. You need the lightest design to successfully fly for a long flight. 2. Drop the metal bearing and simply make a PTFE centre shaft as part of your motor redesign. Both weight and less friction will result plus less leakage. 3. Your use of PTFE is great to reduce friction and also deal with engine heat, but you still need some lubricant to deal with the micro leakage. I suggest providing a amount of light synthetic oil via the central shaft where you made the bearing replacement. The centripetal force will dispurse the drop sealing not only the central shaft and lubricating it but will fly to the outside of your leafs and then seal there to provide seal plus lubrication to the leafs. You thus solve both leakage issues. On a final note, the Tesla Turbine concept which you do not mention (since it applies to fluids not gases) could draw inspiration by potentially using the exhaust gas the the outer edge to a perpendicular disc adjacent to the motor with the disc dimpled with half clam shaped dimples to catch the air but using a logarithmic sizing of reduced clam size as you work to the centre that would be exhaust port. Despite air not acting with the viscosity of liquid as Tesla design, the clam dimples could assist to additional acceleration of the central shaft of the motor. Of course such fabrication was impossible in Tesla days but with a 3D SLA printer it is. The only downside is additional weight to add this and also size since the larger diameter disc provides greater efficiency in the Tesla design. Since you wish to fly, just stick with the original 3 points. FYI - a recall around 2008 when a company out of India called Tata was proposing using air as the new fuel. They did make a prototype car but I think it only went 30km/h and so for small city driving. No clue on their engine design but I always liked the idea of air as the fuel with the exhaust as the air that went in! The question of how best to compress it likely created the additional complexity that we never saw it materialize.
1: that pressure reduction value weights 10x more than the motor itself. A reed valve sets a minimum pressure not a max. How would that work? TATA discovered that the air in India was too dirty and clogged the compressed air engine. !!
@@stephencaparelli7733 I felt so smart when he said that! Maybe I can be an aeronautical engineer after all! But in actuality, I work at IKEA, and yeah, no.
Use less diameter bearings to reduce the area of leakage in them. Also, it's better to have more volume of the engine cuz it improves the ratio volume/leakage.
I believe if you have more volume in the engine the running time will lower because air in the bottle is still the same so % of air that is wasted is higher
Or 0 ball bearings, since it only runs for a couple minutes he could just use teflon sleeve bearings/bushings with some light oil or grease. Also if he was to change the drive shaft to steel he could use a much smaller diameter which would result in lower leakage around the output.
As an engineer I've seen something similar in a marine application here's what I suggest. Use a 4° reverse vein use your pushrod design. Use graphite powder dry for a lubricant and gap filler. Your central peace should be two parts to clamshell against the veins and the pushrod unless you can get tight fitting as single piece. You may even be able to go to a three vein 2° reverse angle using a cam style to move the pins in a direction to keep the veins close to the outer shell. And you could then use a nitrite seal or similar automotive style seal on the output shafts of your rotary vein. That would minimize your parts your escape portions if you do the tight tolerance thing again with the seal it would keep everything much tighter with less friction minimizing your parts and less air gap
Hi Integza, Phi here! I have a bit of experience with vane motors and vacuums pumps. It looks to me like you can solve a bit of your tolerance problems by making your rotor larger, and the vanes shorter, in your flappy motor design. It will give them less opportunity to flex under the air pressure, and allow for you to run it faster or at least more efficiently. For the vane design on the other, narrower vanes are better, but the cavities should be sized such that there are extremely tight tolerances, and when the vane is fully extended there should be about 2/3 of the vane left in the gland, otherwise friction will try to drag it out of its space, causing more friction, and eventually self destruction. Gaskets and rotary shaft seals are grand!!! Three vanes are better than two in all regards. Cheers!!!
This is awesome. I love this little flappy engine; I think you have landed on what could be the new gold standard design. Please check the sealing on the piston's axial direction. If you machine annular flap seals into both piston faces, remember that the propeller is pulling the piston towards the front, so the seals on the back face of the piston will have more clearance. For even better sealing and less friction, you could make the entire expansion chamber PTFE, using the resin housing for structural support. Or just machine a grove in the housings for PTFE o-rings. Finally, your bearing isn't the best one for an airplane. You need a thrust bearing in the front of the engine and a sealed bearing on the rear. The front bearing and engine housing is taking all the load of pulling the airplane forward.
@@orestdubay6508 Yep my 50 year old marine engine used a vane cooling-water pump with "compliant" rubber impeller, It's a far older design than you think. Making it low friction is the challenge here though.
Given the friction, what about making the flaps replaceable tabs that lock in with a key fit, but doesn’t add extra leaks? After enough run time the flaps would wear down like apex seals do.
My favourite video of yours. It's just one good idea after the other. Quickest/easiest fixes: 1. 3D-printed flap mechanism + teflon housing. CNC cutouts around flaps increase the volume of air wasted. Maximize pressure differential vs volume per compartment. 2. Print versions with different amounts of flaps. Finding the correct amount in theory will take forever. Just print versions with 2 up to 5(?) flaps and see what's most efficient. No math needed. 3. Use a liquid, plastic-compliant lubricant. It's basically a free sealing agent. 4. Ball bearing in the center really makes air leakage too easy. Teflon center shaft and a lubed bushing would have just as little friction and be much easier to seal. 5. The front and back wall need to keep the air in the flap compartments. Look up a "labyrinth seal". Perfect for rotating designs, easy to implement, basically zero friction. Add the lubricant, boom, got a great seal. 6. Where is your outlet? It wasn't entirely clear in the video. Just make sure the air escapes quickly after the halfway point, otherwise the engine is working against itself. 7. Housing with a nautilus shell shape, but with a very smooth transition, so it doesn't wreck the flaps or cause them to catch. Then you can use almost the full rotation for expansion. Adjust outlet position accordingly. 8. Make sure the back wall is stiff enough to make the deformation due to axial force from the prop negligible. Otherwise sealing the flaps will be even harder. 9. Ideal energy extraction: You're extracting elastic energy from the air pressure. Once the air pressure inside the compartments is at zero relative to the atmosphere, you've taken all the energy out and can reset using the exhaust. If you're starting out at 2 bar, that means you're at 3 bar relative to a vacuum. If the volume then triples between input and exhaust, you'll be at 1 bar relative to vacuum and 0 bar relative to atmosphere. There's your formula. Rocket nozzles work on a similar principle. Those are all the easy ones. Good luck kicking Tom Stanton's 🍅 (Both of your channels are great, but trash talk makes the challenge fun.)
The little flappy flaps are an excellent addition! I'm also really happy to see you finally put a regulator in the system! You saw immediately how much more consistently the engine ran. I now want to see what happens when you add more of them - 3, 5 or 7 vanes. Most fans use an odd number of blades to help reduce vibration, but I think a higher number of blades will give you better static pressure, and drive the prop better.
Hello, in order to reduce leaks between the transparent plate and the rotor, you could install a series of 2 or 3 baffles, they are used in applications with very high rotation speed and high pressure. I remember this passage from my engineering classes. With the tolerances of your printer this might be possible. (sorry my english is bad it's not my native language) Edit : There is no friction with this solution, because the two parts do not touch.
I was thinking some matched up oil grooves for the same leakage points. since it's a short duration doesn't matter much but needs sealed. and a frigging o ring around the main body and clear plate. once the spinny bits are better sealed, that body is going to be the next spot.
Given the leakage occurs through the bearing, the bearing itself could be extracted from the main piece. It would be kept aligned to the rotation center axis, but only sustaining a center rod with minimal radius to be sealed against the pressure chamber.
1 Upgrade to high-quality sealing materials like silicone or rubber to keep air from leaking. 2: Redesign the valve system using CAD software to ensure smoother air flow and efficient operation. 3: Use the Teflon rotor directly as a bushing, eliminating the need for bulky bearings. 4: Adjust the exhaust port design in your 3D modeling software to better match the angle of the vanes. 5: Incorporate heat-resistant filament materials, like ABS or nylon, during the 3D printing process. 6: Integrate noise-dampening materials, such as foam or silicone, into the motor housing. 7: Choose durable filaments like PETG or carbon fiber-infused for 3D printing to withstand pressure. 8: Calibrate your 3D printer to achieve precise layer bonding and avoid defects. 9: Post-process printed parts by sanding or using a chemical smoothing agent to reduce friction. 10: Design parts in a modular fashion, making them easy to replace or upgrade in your CAD software. these are sum ways you could do this i guess
I LOVE LOVE LOVE that you took on this challenge. The pneumatic engine removes combustion dangers, allowing everyone to try new ideas on one of the most useful components of the modern world. Converting stored energy into mechanical rotational energy. Years could be spent tinkering with pneumatic engine designs. Its incredible the varied possibilities that exist, things that have never been thought up just waiting to be discovered. My favorite video EVER that you've created. Except needs more exploding "Tom"atoes.
A way to eliminate some of the leakage as seen at 12:40 can be using sealed/shielded ball bearings or even better, fluid shield bearings! not only it'll eliminate the bearing leaks, it'll help the engine run smoother since the bearings are constantly lubricated.
Since the flappy engine has so much less friction, have you considered going back to a three vane or four vane, that way more of the pressure that’s coming in has a smaller expansion area before the next vane kicks in, I may not be explaining this correctly but a third or fourth vane should give it more torque and or speed, just note this is an idea before the end of the video, timestamp is 18:37…never mind I just realized the total length of the video😂
Also trash the bearings, instead make the rotor with the “shaft” built in and in the main block just have a blind hole and do the same on the front cap. That drops the leak area plus with it being made from PTFE, shouldn’t be much friction!!! {-o-} diagram for example!! Love your channel, and Tomatoes are totally gross!
That confused me... I'm not understanding how they were both always in contact with the outer cylinder, when they were spinning in an offset radius; was there a spring in that shaft?
@@userzero9259 it doesn't matter that it was offset, all the matters was that they stay the same distance. if you're good at visualizing, imagine focusing on just the rod. it doesn't matter what else is rotating around it, it's just getting pushed back and forth from the pivot's POV
I LOVE the childlike naiveness of youtube comment section. It's not like pneumatic engines have been practically solved for years if not decades and literally anything seen in this video isn't new nor unkown to the content creator beforehand. He's not even that good at pretending coming up with new solutions or being surprised at things like..... not using any lubricant, LMAO.
The whole point of a tesla turbine is to blow air directly on a set of discs, so unless you mean "scrap everything you were doing to make a Tesla Turbine instead", the mechanism he's using inside is taking up the exact spot he needs to make a turbine with.
Quick, simple, and requiring no major container changes: Increase the number of flaps. I KNOW you reduced the VANES to 2 to reduce leakage; however, flaps are different because the pressure increases the seal. Thus, more vanes means more torque AND without sacrificng sealing. NOTE: I am NOT suggesting going from 2 to 3; rather I AM suggesting seeking a sweet spot which might be 3,4,5, etc. to find the optimum between the net increase in friction with the net decrease in leakage. You MAY need to simultaneously seek a sweet spot with regard to pressure as well. Hope this helps. BTW, I love your presentation style.
i think it very much depends on how much friction each vane/flap causes, if there are two pressurised cavities (implying 3 vanes/flaps under some pressure) then the mid vane has pressure on both sides, albeit that the pressure in the cavity nearer the inlet ought to be greater than the cavity about to exhaust.
It's not that simple. If you have too many the airflow into the chamber gets cut off too soon. Most energy is probably extracted between 30 and 60 degrees after the inlet. With two flaps the movement after 60 is not helping much. With four or more you are not maintaining full supply pressure throughout the productive part of the cycle. It could be calculated more rigorously but my gut feeling is that 3 may be the optimum. You are right, his reason for moving to 2 has gone, he need more flaps.
@@nomdefamille4807 Thank you for your well considered response. In my mind I pictured sort of a water wheel -- but you may well be correct. I am not much of an engineer; I have always taken the million monkeys approach -- admittedly, more tortoise than hare; but it usually works in the end.😀
@@nomdefamille4807 Thank you for your insight. You are obviously a much better engineer than old kitchen chemist me. I had visions of a sort of water wheel efffect; but, that just might be the amateur in me. I still think something along those lines might be worth a shot. Who knows; even if it fails, it just might provide some iterative inspiration. 😀
@@tuberroot1112 FYI Commercial vane motors can have up to 10 vanes. It appears to be a judgement about lower friction vs lower internal leakage and RPM. As long as the vane still has space to expand outwards then the air can continue to expand. Given the inner rotor is offset from the outer, the rotor can rotate 180º and continue to expand.
What a great take on building and improving a pneumatic engine. I am no engineer, but here are some improvement ideas: - Reduce the overall weight of the rotor and the thickness of the wings to reduce the friction - Reduce the leakage between the rotor and the case, maybe with some gasket or sealant. Maybe a graphite or carbon based lubrificant? - Consider tweaking the area of the chamber versus the area of the wing, there must be an ideal ratio to improve efficiency - Change the shape of the wing to a "C" shape in order to optimize trust, like a water turbine Awesome video (as always), cant wait for part 2. Keep up the good work Best regards from Évora ;)
Seal the bearing, use a high performance ceramic bearing, 3d-printed bolts for lighter weight, create a turbo charger for the engine. Like a rotary engine, use a center block housing essentially using two engines and combining them into one. (Dual rotor). But the simple answer is to hollow out the circle piece under the flaps to allow more air underneath the flaps and more air to fill the gap creating more power, this also lowers the weight significantly. If you make a dual rotor style design, to solve this offset in the engine, offset each block opposite to the last to balance it out.
Yeah he went dual veins because of sealing and springs and kept it as he went to flaps but with the flap designs there is no reason to keep only two veins. Not sure if more veins will help getting better results but it should be tested for sure.
@@gg4760-k5n Three vanes will probably help, because as-is air inflow can leak over the back of the rotor to reach the exhaust and lose pressure. Three sections will allow a filling section, a power section, and an exhausting section.
more longer, thinner flaps makes for turbine, but that'd be heavier and brittle - engine that works till first touchdown? 2. Do we really need to sal friction of teflon against teflon? Doubt.
add a ball valve before injection, reduce chamber size, make a spiral to open and close the ball valve only when you need it for the amount of air needed to achieve the rotation you need.
Issues to correct if you want to use this in a plane: 1.In the engine where thee air get in make it a little thin and set pressure to 3 bars. (so it works like a water jet cutter, generating more thrust) 2.Optional:- Use silicon glue to fix leaks 3.If you can try a 4 vane engine
If you also put the flappy flap on the side the engine would have an even better seal. Also, test again with 3 or more flapy's at a lower pressure. Maybe you can increase the runtime even longer.
Add a casing around the motor and connect the intake to the space between the motor and the casing. This space will then be pressurized, preventing air from leaking out of the motor. It is particularly important to ensure that the shaft penetration is properly sealed.
That is absolutely brilliant. Your engine might be more efficient with 3 vanes or a side inlet valve to allow the compressed air to uncompress in the chamber before being expelled. I have another suggestion. Instead of running the compressed air engine using a bulky soda bottle filled with compressed air, try running it with a dry ice battery. This is small pressure container with some dry ice in it. As the dry ice evaporates and releases CO2 gas it cools the container, which reduces the pressure in the container. To maintain the desired pressure a tiny fan blows air onto the container to raise the temperature of the container. So the speed of the tiny fan regulates the pressure and power output from the battery. 100g of dry ice releases 54 liters of CO2 gas.
To improve this wonderful tiny thing: 1. Center the air intake as much as possible for the airflow to hit the flaps (it's not about max torque, but about the air efficiently pushing them) 2. Make the flaps into a pelton turbine shape: if it's efficient for water, it's probably great for air too! 3. Get a bearing with a rubber side: a lot of pain was leaking through the bearing! 4. as @naasking was saying, experiment with 3-flap design and try to reduce back pressure 5. find the optimal width: with eiter software or a couple of prototypes, surely there is an optimal width that maximizes torque without killing rpm. I hope this helps! Much love from Italy!
the traditional pelton wheel gets its advantage over the venerable water wheel by providing a course for the fluid to reverse direction in to an "unconfined space", so for that aspect the air needs to leak out. here i think he needs the torque of the "rotary piston". if he is currently running for 3 minutes against a need for 2 then he could open up the inlet nozzle slightly and increase the depth of the rotor/ motor. he really should try and dump the regulator, the assembly would better use the stored energy if it could withstand peak soda bottle pressure. and in terms of flight performance anything to reduce weight, as all others have pointed out.
@@dziubo1 I suggest you go and have a conversation with Mr Bernoulli and ask him to explain his gas principle to you, then you might be able to answer your own question.
3D print a seal on the ball bearing, similar to a sealed bearing (or try a sealed bearing?). I suspect that reducing this source of air leakage will help. Also try adding oil into the chamber before you screw on the cover, instead of just pouring oil through the bearing. This oil may help take up some of the tolerances.
Please make a version 2 of your turbo jet engine that will run for longer , it was one of ur best videos, I too felt the joy when it started working , plsss.
Make the rest of the shell out of Teflon, possibly use a Teflon bushing to seal the output axle to the assemble face to prevent air leakage from the bearing which also drains the lube quickly.
A couple of things that should help. 1. Switch to smaller sealed bearings over the open face you are using. If you take the seal disk out of the bearings wash them out and repack with a thin and I do mean thin PTFE grease. 2. When machining leave as much material in the hub. The voids you have made in the hub are pressure vessels as they go from high pressure to low pressure you're losing efficiency and air volume. To minimize surface friction where you have through holes just make a small depression half a millimeter deep so you create a smaller pressure vessel and cut down on surface friction area. 3. Use smaller diameter end mills when cutting your flat veins so the volume of material removed is smaller therefore cutting down the static displacement of the chambers.
Hey there! I just watched your latest video on the compressed air engine, and I have a few thoughts and suggestions. First off, you removed one vane, leaving only two, and replaced them with those floppy things. Remember, as you mentioned before, more vanes generally mean higher RPM and power. So, have you considered adding more floppy things instead? Speaking of improvements, why not try lubricating the engine with graphite? It worked well for the rotary engine in your previous video, so it might be worth a shot here too. During the leakage test, I couldn't help but notice some noticeable leakage around the bearings. That might be something to look into. I'm a bit curious about your end goal here. If you're aiming for maximum flight time, the two-bar setup might be sufficient. However, if I were in your shoes, I'd consider increasing the pressure up to 2.5 bar for better power output. Lastly, when you eventually get this contraption airborne, I wonder if the pressure regulator might be too heavy for successful lift-off. Have you considered its weight impact? Keep up the fascinating work! I'm looking forward to seeing how this project develops.👍
Yeah I know, but I'm not English. I'm just shit at writing in English. It's also not necessary I mean no one will ever read this besides you. So yeah the translator does the thing for me.
If you keep if named flappy valve it should probably resemble flappy bird! Could you replace the vane system with a compliant mechanism? For optimization: I think you can change the expansion chamber to be more round and have a better flow profile. Second, you could adjust the volume of the expansion chamber. Third, adjust the amount of flaps. Optimizing these could produce a higher rpm and longer run time.
Now that you have eliminated the veins, you could lighten the rotating mass by drilling/milling holes in in a bolt circle around the bearing without compromising the integrity. Your videos are so good. Thank you.
Nice idea! Have a back half and a front half. Front half would just be a front bearing and crankshaft to the propeller. Connect the two rotating parts via magnets. The issue would be you'ld want strong enough magnets to keep the parts connected but not so strong they tried to clamp together causing friction.
I want to say no, that won't work but I can't think of any reason it wouldn't that couldn't be overcome with some clever design. At least for very low power applications like this. Yeah, I can think of several things that would prevent the motor working but they are all things that could be solved easily. Nice idea.
If you go back to vanes, using more vanes would reduce the leakage area. You could use the opposing bar in a cross configuration for 4. Use cylinders at the tips to seal against the wall. If you cut ratchet type notches in the cylinders, you could use the air trying to leak to push the vanes harder
Love seeing compliant mechanisms. I wonder if the outer housing could be more optimal if it isn't round, to maximize the force applied to rotation over leakage.
You should check out the Di Pietro Rotary Air Engine. It operates on a principle similar to the pneumatic vane motor, with greater efficiency but can be harder to manufacture,
This video was one of the best you did this year. I feel like a lot of times you only try a few prototypes and then end it, but in this one you kept trying and trying and making adjustments and more prototypes and it was such a great journey! I would love more videos about air engines.
To make it better: use your flappy seal design to make seals against the front and back ends between the rotor and the wall. Also, build your own lightweight pressure regulator. It might not actually put out more power, but you can make it lightweight so that it could actually fly.
You should make an radial lip seal that closes in the axial direction towards the bearing as part of the front of the transparent housing behind the bearing. Or an axial shaft seal. .
oooo an engine that works via compliant mechanisms, that's fun! Biggest issue I see is that you probably have quite a bit of wear on this engine, even with such a low coefficient of friction, right? As long as it runs, it runs great, but eventually the pieces will wear down so much, you get too much leakage again, I think. With the flexure version you *could* try going for a three-finned variant again. Might be even better? Though two-finned seems to work rather well
To increase durability, you can make the flaps longer. Right now it looks like they are just about the ideal length for maximum leverage without leaks, but when they wear down it will very quickly start leaking since the flaps won't reach the edge anymore. So for a more long term engine, I would add maybe 2mm of length, slightly decreases efficiency but makes it much more reliable over time.
by making the flaps longer you gain a certain amount of built-in wear resistance the flaps may wear down, but they have to grind through the whole extra length of the flap....
@@Kram1032 as long as they aren't so long that the cross section of material touching the wall increases, it shouldn't be much more. however, if the flap is too long or thin then then it will overcome the strength of the teflon, sag and drag excessively along the wall
One of the nice things about Tom's was it could be made at home simply with a basic 3d printer and not require much extra machining work. But it is nice to see that the step up from his to yours really isn't out of the question for someone with a bit mre tooling availible.
Vent the exhaust into a second (smaller) motor of the same type to more efficiently use all of the air pressure. To make a better seal against the top and bottom of the motor, use a rounded surface on the top and bottom of the main rotor and sand a concave divot using the the rotor in the same way you explained in the video and use bearings that have ceramic or gem balls along with a seal over the race.
I don't think you need a second turbine. If theres a 2 bar input, you just need to make sure that the chamber doubles in size in between the input closing and the output opening. Yes if you were working at very high pressure, where this wouldn't be practical, make it double or triple expansion. I also wonder if an air bearing would be better in this situation.
When I buy any 'cheap' air tool, I run it for a baseline, then tear it down and check everything using a granite surface plate and Prussian Blue. Once all the parts fit, lapped, sharp edges chamfered, orientations to ports corrected, that cheap $20 tool will almost always perform like an expensive brand name tool. Love your flappy design and your follower vane, I can see real world applications in my future.
1 - Make the central shaft out teflon and lap it to a free spinning fit with the housing to eliminate the bearing. 2 - Use 2 very thin teflon washers that are recessed into the housings on either side of the piston and have an interference fit with the drive shaft. They provide a bearing surface, seal, and any bypass ends up being used like a Tesla turbine. 3 - Print the piston out of the most flexible material you can with a small cavity in the ends of the flaps to insert a small bit of teflon. By 3D printing you make the chamber size smaller for higher torque. Flexible material suggested for longevity. I'd probably go with a long triangle of teflon for the insert to provide the smallest friction on the wall of the housing as well as creating a pressure seal on the flap socket. I agree with others that more flaps would be a good idea. I'm thinking 3 or maybe 4. I would be really interested to see the entire engine changed to a Tesla turbine with the exhaust port coming out of the rear of the drive shaft to scavenge that tiny bit of extra thrust. Though I guess any pneumatic motor could be ported for a similar effect.
One thing I could suggest is giving the flaps tension against the housing. If you want to nit-pick; then there's going to be a resonance frequency for the bump/rebound of the flaps in which you'll hit optimal seal at a specific RPM. I would also test having a third flap, and if you hadn't already, slotting the exhaust along the entire recoil arch.
you could probably get more rpm if you added a few more flaps and measure at what point the amount of friction from more flaps decreases the efficiency. Great idea though and beautifull you made it work.
For many years now I've been thinking about the ultimate air compressor with no moving parts. It would involve several pulsejet engines, long enough so that they would transform the deflagration into a detonation wave, acting as supersonic PDEs (pulse detonation engines) distributed radially in a star configuration, or parallel to one another like the chambers of a revolv*r cylinder, facing a pressure tank. They would repeatedly fire one after the other in a circular pattern sequence, a bit like a Gatling but with no physical rotation, maintaining the high pressure inside the tank, which could be used to feed the nozzle a Coandă disc aka Aerodina Lenticulară (but this one his another story…). Indeed, the equations of fluid mechanics have two parts: velocity and pressure. For the past century, the various successive engines developed have favored the exhaust velocity over gas pressure. But the very first engine, the pulsejet, did exactly the opposite: it imparted a lot of pressure to the exhaust gas, and relatively little velocity. The high pressure of the pulsejet engine, and more exactly its modern iteration the PDE, could be leveraged to impart a great pressure into a tank, with no moving parts (or maybe just servoflaps either electronically or better mechanically controlled) with a very good power/weight ratio. If only I had a 3D printer to build the prototype!
What about combining rocket engine and compressed air engine. For example, making a system that produces giant amount of reserve gas that could power the engine for a long time with relatively small mass. See, you can only pump so much air into two bottles, but storing potential gas in solid form, in my opinion, is a very interesting idea. I am thinking a slow burning solid state rocket motor that does not produce thrust, but rather accumulates and compresses exhaust gases?
The flaps could be made more robust as a pivoting hinge (it would probably introduce another leakage point, but might be worth a try). The hinge would just be a cylinder embedded in the circle. From the top, the hinge would look like a comma, with the circle part of the comma inserted into a corresponding round cavity in the rotating circle.
You should look into how sealing forces work in a vane motor. Basically, the fit of the vane in the rotor is not important since the air pressure will force the vane to one side of the slot (and out towards the housing). The end play of the vane in the housing is very important, on the other hand, as a gap there provides a straight leakage path to atmosphere with no inherent sealing forces to counteract it. Also, the vane should sit deeper in the rotor, the length inside the rotor should at least be greater than the length outside of it with the vane fully extended. This will both reduce friction from the vane tipping over and eliminate the need for springs. In the end, your choice of a compliant mechanism eliminates all of these aspects except for the end play which must be carefully controlled.
if he's anything like my brother-in-law, who's also lifelong repulsed by tomatoes, then no - sauce is fine, it's really just the texture of raw tomatoes that scratches their nerves.
1. You can try to change inner diameter to find a sweet spot for friction forces vs air waste rate, to find a better energy efficiency. 2. Add silicon grease inside (not a spray)
Put in another intake valve next to the one you have. Take a tube and feed the exhaust from the motor back into the cylinder at the new intake. Re use some of the compressed air for a longer run time
combining some ideas here: 4 vanes with two rods for balance reasons, engine is pulsing with only 2, one rod higher than the other so there is room for clearance for x shape without intersection. reduce weight by replacing bolts with something lighter, maybe bolts made from same material as housing, or weld with epoxy, grease the bearings ofc but usue something viscous because that will help reduce leaks a tiny bit, see if you can reduce weight on the chassis somehow, maybe a thinner teflon layer and a composite outer layer glued together with epoxy for weight reduction, try removing the shaft instead making the shaft and crank assembly a solid piece. make tolerances tight and run it with the abrasive until it becomes self compliant.
1. you could reduce the radius of the blades, that could save some weight. 2. point the exhaust backwards or down to gain extra thrust 3. increase to 3 or 4 'flaps' to catch more air
4:41 You timed it without any back pressure. Once it has a prop on it, the motor will run slower, increasing the running time. You can use a bigger nozzle.
It's just a standard air tool motor. Your seals are two wide at the head, this creates friction. You also need to oil it through the air inlet port, this will help with sealing. You need to use a high quality sealed bearing. They usually use phenolic sheet for the vanes. The rear edge of the vanes are shaped in such a way that it helps the other edge seal against the bore face.
i love the idea , 2improvments i would make is 1. an exit tube to take the extra pressure and put by inlet with a pressurized T 2. when it starts generating to much pressure it would deliver the over pressure valve making it go back to the air bottle allowing more pressure and more air to make it last longer.
Hello, these are some of the improvements i think you can make... 1. The method you used to obtain a perfect fit to reduce the air leakages, you can use the same method for other parts. 2. Increase the no of flaps to 4-5. I think 3 flaps will be the best. 3. You can have multiples inputs (all of the same pressure). no of flaps = no of inputs Thats all I have to say.This is an incredible build. HUGE FAN OF YOUR WORKS INTEGZA❤ WATCHED ALL OF YOUR VIDEOS AND HPOE TO SEE SOME MORE JET ENGINES😊
For the plate leak on the face and back of the engine, you could hollow out the center of the teflon vane rotor and place a trough. I don't remember specifically how it works but very small troughs that are like deeper REALLY reduce leakage and it would REALLY lower friction on the face and back. also if you want it to fly you'll need to reduce weight but any number of things can do that
You forgot to include colored fluid leak test footage. For upgrades I suggest: 1) put thin, bit oversized rubbery sheet on the flexvane to form lip seal, or copy the process of making lip seal from Tom, 2) seal the rotor - either between rotor and sideplates or shaft and hole in sideplate - I think Viton xring would be best but NBR oring should do or do lip seal again, 3) lube everything, but not excessively and check material compatibility just so parts won't start degrading 4) do a long run test to improve living hinge design of - it may be subject to fatigue failure, 5) add more vanes for smoother opeartion, though I don't know how that influence efficiency, 6) check if position of outlet is correct - I have the impression that waste air is compressed a little, 7) noncircular chamber to lenghten expansion angle; current design is at 180°.
More vanes more power. More efficent use of energy. What is amazing about your flap idea is you can have many more. Try putting the flaps at an angle. Also using a softer material for the vanes than the casing is advised. So it whittles em down sealing a gap. Think how a brushless motor works. Then design the flaps to still make perfect contact while they whittle down over time.
To improve performance and reduce weight: 1) Use carbon fiber for the housing to cut down on mass 2) Add precision rotor seals to minimize air leaks and boost efficiency 3) Experiment with a hollow rotor design to reduce inertia without sacrificing strength. Imagine how much faster and more efficient it could be! Also Maybe you could do a collaboration with tom Stanton to improve this engine more and Maybe build the best air engine in the world
The biggest leaks near the end seemed to be leaks between the planar surfaces, or to put it another way. The air seemed to leak between the rotor and the clear surface on the front. If you make the rotor slightly wider than the side walls, add the abrasive, and then spin it with those being pressed together you can probably achieve a better fit.
You could try to increase the area of the flaps relative to the leaking e.g. by increasing the depth of your motor. And to harvest more from the power stored in the bottle you could ditch the pressure regulator (essentially throwing away a lot of stored energy) and add a motor, which can be switched from series to parallel pressure. Make the full housing air tight (including the bearings). Hope that helps.
The leaks occur mainly at the ends of the rotor. A longer rotor will have a higher ratio of vane surface area to leak area. You could also use labyrinth seals between the faceplate and the rotor to reduce leakage without increasing friction.
Yay!! Missed you Hermano! Always made sure to check your channel to make sure I wasn't missing out! One day I will be able to do some 3D printing as well!! Ideas 1: Make a 3D printed water turbine for small creeks and streams. That would get you out of the house and help people in rural/poor areas create some power! 2. Make 3D printed outdoor sensors! A. Tree\plant growth monitors B. Soil Moisture content C. Wind Speed/Pressure D. Soil/Air Temp E. Insect detectors/counters F. Spore Detectors *Make them self sufficient and with drone beacons to direct drones to water/spray insecticide/fungicide on the plants!
Let's discuss improvements: 1) go with a spherical rotor rather than disk rotor, 2) use a lifter valve to control outflow, 3) use trapped flaps or valves (a trapped valve is one which is framed with guides to either side. Hard to do on a disk style rotor, but on a spherical rotor, the points of the sphere merging to the shaft can have guides placed to oiled channels within the chamber, which act as permanent wings. The valves extend down between the edges of the frame, ensuring smoot movement and proper contact to the chamber wall). 4) Stepped chamber contact. The wall of the chamber should be contoured to the valves and the rotor. (Be it a disk or sphere). Even if you do continue with a disk rotor as you have done in this video, the valve and wall should meet each other at a contoured position. This improves contact stability at higher RPMs. 5) Nanoscale plaining: while you likely can't achieve this at home, if you were to design and print parts from your friends who print with the nano-porous stainless steel, you could achieve far higher tolerances thus improving efficiency. 6) Use contained magneto bearings. Disk vs Sphere vs Cylinder design. Efficiency and stability are key, and one of the biggest issues with your design is stability, with a great deal of leakage. The valves you have aren't sealed within the disk, and the disk is too close to the bearing to prevent major leakage. As you demonstrated when you use the component to component grinding method to refine the gaps, too much pressure can build up causing the engine to break. Using either a sphere or cylinder that is longer than your disk design could resolve these issues. For example, you can create a buffer zone with both the cylinder and sphere to reduce pressure on the bearing and drive shaft while improving internal leakage. The extra length of both gives you wiggle room to adjust pressure controls. My final thought is simply to switch to a magnetic bearing system, and isolate the drive shaft from the internal workings of the rotor. This should work even with your disk style rotor. Use neodymium magnets in opposition to create a magnetic suspension for the rotor on both sides at the appropriate position within the chamber (the offset position). These magnets can be situated to not only act as the bearing for rotational movement, but as side to side movement (jitter). On the end that will attach to the propeller, use a normal bearing to anchor the propeller and driveshaft, and then use magnets attached to your rotor and an external disk connected to the drive shaft of the propeller. In this way the propeller will not be damaged or ejected incase of blow out, and the rotor can spin faster than the propeller while driving it. (Magneto induced rotation is used in water proof applications all the time, including power generators). By using magneto bearings and a magnetic drive system, you can eliminate all external leaks and control air outflow as specifically as you want.
To maximize the efficiency, you should try to maximize the pressure difference between the injected air, and the exhaust air. (i) Put the rotor axis closer to the edge, i.e. make it more eccentric, (ii) make sure the air starts injecting at the moment when the cavity between the flaps is the smallest, and exhaust opens up when it is the biggest (this depends on the number of flaps you have), (iii) add more flaps (this comes with a friction drawback tho). All this assuming you work with high pressure, if the pressure is low, make sure there is no less than 1 bar at the exhaust.
To get rid of the Heavy screws that make the plane harder to fly: try to use some glue. This would also prevent leakage to the outside. Since the walls of this are thick too, you should try to make them thinner to lose weight. When using bottles, the bottle should be as near to the engine as possible in order to make the airflow faster and the way air has to travel shorter, reducing friction and loss of pressure. And the easiest way of making a bottle last longer is increasing its size, say to 1.5 litres. Bottles of this size don’t weigh much more but can store more air. Using a ring of rubber in the area between two parts can also decrease leakage
Hey Integza, I figured I'd throw my hat in the ring after I gave some improvement ideas I had for a rotary vane engine to driving for answers on my how a 3d printed engine (about 3hours something in) caused a dwarf planet to hit us. But suffice it to say the sides are your biggest issue, you're studying in school I'm sure you already know that. Same thing for how friction in the system is just ridiculous thanks to needing a sealing material that is constantly rubbing at different pressures and velocities. How does the air come out!!!!!! So! The easiest way would be to make a oil bearing that uses sliding linear bearing towards a center that allows for a crank gear axel to rotate. That's the layman's explanation. Oil on the inside diameter of the housing with a circular grove cut in to the side to have a type of 2 piece "mushroom" bearing area would work best for this design. Or even a flat circle that uses T cut sides to have the plastic (or metal) forced into oil that has to go around multiple right angles really increases the seal. A few offsets air channels allows for the oil to be separated during the airflow into the intake, like an oil catch can. With a few rings on either side of the housing this fixes your leak issues & the vane movement issues. Mostly, nothing is perfect, some oil will get lost & as such it wont be perfect. The ring that is the bearing just needs some holes and threading to allow for the plunger based axel, like you were using in this video, to self align. However!!!!! Using a vacuum would help you have it transfer faster, but that's more difficult so instead a fluid that is lubricative is usually going to be better. Some small o-rings technically work, but they are prone to degradation, so a simpler system of oil traps that squeeze the oil through holes in the spokes would work better. Several tubes basically with some small holes, like you drilled on the video, will work placed in a larger tube that are the spoke housing with help keep it sealed using old school 2 stroke engine tech. Here's how the air comes out. The air has to come out through change of the 2 stroke engine hole placement on the outside spokes. It slides down enough to expose holes that lead to the housing area that has the spokes poking out and sliding around in the in-between area of the 2 halves of the housing. That allows for you to put a manifold around it to use as a scavenge (Bernoulli's principle here) effect for flowing air to help with air coming out to further increase efficiency. As the spokes poking out can now help "seal" a little (not much its mostly to create a type of flowing directional air to aid in this effect like your initial prototype design nozzle ends that spin the center) of the air in the system that might get trapped and start flowing directionally towards the exhaust, but now with air from the outside helping a little using some side air channels that have simple intakes and that all run towards the exhaust point. As it travels towards the exhaust, the spokes rotate, and more air continues flowing it grows more efficient. Especially if it was a plane flying, or car! Wooohoo! The video is on my Xenon reality channel.
You don't need a ball bearing when using PTFE. A smooth rod is good enough. And if you machine a small groove juts a little ways from the hole, and put a small O ring, greased with silicone grease, in it, you can get close to a perfect seal. Also, now where you have non-leaky "flap" design, I think it's worth experimenting with more flaps. Many more flaps. The available volume is constantly expanding (in the direction of rotation) so the pressure will always be the greatest on the flap facing the previous "compartment". Having more flaps will get you smaller amounts of air lost when they pass the exhaust outlet, so going as high as the geometry allows would be my first test.
As most have stated the housing can be made of teflon as well. Using a near interference fit for the shaft holes and let it run with the abrassive compound to wear in the shaft and housing to create the same near perfect seal. The rotor inside can be made to touch the case and wear in as well with the same method. This would make all of the parts fit to each other as closely as possible to seal off any leaks. Once the engine design and rotor assembly are perfected then worry about sealing the front doing away with the bearing or running a piece of teflon behind the bearing to seal bearing. Or spend the money for sealed bearings......
I think for the rotor-piston, you should put a teflon, or similar, washer seal/gasket between it and the front/back of the housing. This would drastically reduce the amount of air seeping "around" the piston on those two faces. I would also recommend increasing the "hinge" of the flaps just ever so slightly so there's less fatigue on the hinge.
Get an exclusive 15% discount on Saily data plans! Use code Integza at checkout. Download Saily or go to saily.com/integza
Yes bro ❤❤
Thank you❤
PLEASE MAKE A ROCKET TURBOPUMP!!!!!!!!!!
PLEASE MAKE A ROCKET TURBOPUMP!!!!!!!!!!
PLEASE MAKE A ROCKET TURBOPUMP!!!!!!!!!!
Let me know when you get it flying 😉
Would love to see an in-person competition between you two ;)
He can't get it to fly
Do a competition for a video
He have all types of engine in the world but no practical use of it all he does is burn tomato atleast ur ones fly
i reckon get the 3d files , make the engine ,AND FLY
0:30 shots fired 😆
Nice
6:32 with the subsequent "I'm screwed"
Oooff 😂
lol, Hi project air love your channel
U gotta hop on to this challenge i want to see my maker youtubers compete
Issues to correct if you want to use this in a plane:
1. It weighs too much. Make it thinner, eliminate all of those bolts.
2. The shaft bearing is too large and bulky. Do you even need it? The rotor is made of Teflon which has low friction so maybe it can act directly as a bushing. Might help with sealing too.
3. Maybe go back to a 3 vane design now that you've changed the mechanism.
4. Experiment with different geometries for the exhaust port to exhaust faster and reduce back pressure. The vane is on an angle, so the exhaust port can match that angle across the whole vane length to the rotor along the swept area.
Bro, let us come with some genius solutions as well!😂
Somebody paid attention in their physics and engineering classes.
Check out the type of air seals used in jet engines. labyrinth seals. Also I forget what they are called. But there's little indented rings around mortar shells. Those help trap the gas without any friction with turbulence.
Of course both jets and mortars have a lot of gas so leaks are less of a worry than people think.
But there might be something worth stealing because they are both incredibly low friction.
He could also experiment with angling the vanes themselves, the same way the flaps were angled.
My first thought was to increase the number of flaps, but I see I'm way too late to post it.
Integza, about 23 years ago as my thesis project for Mechanical Engineering Technology, my friend and I designed a 4-bar mechanism that solved this problem.
We called it the QRP or Quick Return Piston, because it had a 270 degree downstroke and a 90 degree upstroke.
I still have the files and paper if you are interested.
Simply fantastic work!
The pressure regulator acts like a restriction in the feeding line. The pressure drop is wasted energy (deltaP X Flow). You can compensate the pressure variation (and, thus, torque) changing the excentricity of the engine
Higher the excentricity, higher the torque for the same air pressure.
Note that, initially, when you have higher pressure,you will need a smaller excentricity to generate the needed torque. Lower excentricity leads to lower flow, thus reducing compressed air consumption.
When the air pressure is low, at the end, the excentricity is increased, sustaining the needed torque for longer.
This can be achieved with a movable engine housing, actuated by the inlet pressure
Look for "variable displacement vane pump"
Greetings from Brazil
So here we go.
1. With only 2 vanes, the engine is pulsing. 3 or 4 would increase the surface area to catch the air.
2. The ball bearing is overkill, make the case tight around the shaft. Experiment with o rings or a ledge.
3. If you're regulating the pressure to 2 bar, then you can reduce the thickness and weight of the housing.
4. Instead of vanes, you could use disks. Alot like a tesla engine just small enough to save weight.
5. Rotating mass will be your friend for extended run times due to the light weight. Attaching the propeller with a larger single bolt will help the fluctuation in rotational speed.
6. Inceasing the size of the exhaust port would allow the air to easily escape, increasing the pressure difference on the inlet which would increasing torque.
All in all, a really interesting build and your build process is really relatable. Keep this series up until you battle Tom for air superiority!
The compressed air tools using this mechanism do usually have at least 6 vanes. More vanes will add friction but maybe still worth it?
If you add 4 flaps, you can also add 2 more inlets and exhausts (twice the power for twice the consumption)
More surface area more flaps makeit into a turbine
@@ns-li4pr Yeah, it's already half-way there with that tangential inlet port.
@@-danR The inlet Port should be putt more into an angel. Maybe 10° more degree towards the roation and three flaps. So the Air pressure is directed to the Flaps instead of "filling" the room.
Several improvements are possible:
1. Drop huge 2 psi valve and resort to using a 3D printed reed valve integrated directly in the motor. Why? Weight. You need the lightest design to successfully fly for a long flight.
2. Drop the metal bearing and simply make a PTFE centre shaft as part of your motor redesign. Both weight and less friction will result plus less leakage.
3. Your use of PTFE is great to reduce friction and also deal with engine heat, but you still need some lubricant to deal with the micro leakage. I suggest providing a amount of light synthetic oil via the central shaft where you made the bearing replacement. The centripetal force will dispurse the drop sealing not only the central shaft and lubricating it but will fly to the outside of your leafs and then seal there to provide seal plus lubrication to the leafs. You thus solve both leakage issues.
On a final note, the Tesla Turbine concept which you do not mention (since it applies to fluids not gases) could draw inspiration by potentially using the exhaust gas the the outer edge to a perpendicular disc adjacent to the motor with the disc dimpled with half clam shaped dimples to catch the air but using a logarithmic sizing of reduced clam size as you work to the centre that would be exhaust port. Despite air not acting with the viscosity of liquid as Tesla design, the clam dimples could assist to additional acceleration of the central shaft of the motor. Of course such fabrication was impossible in Tesla days but with a 3D SLA printer it is. The only downside is additional weight to add this and also size since the larger diameter disc provides greater efficiency in the Tesla design. Since you wish to fly, just stick with the original 3 points. FYI - a recall around 2008 when a company out of India called Tata was proposing using air as the new fuel. They did make a prototype car but I think it only went 30km/h and so for small city driving. No clue on their engine design but I always liked the idea of air as the fuel with the exhaust as the air that went in! The question of how best to compress it likely created the additional complexity that we never saw it materialize.
gasses ARE FLUIDS!
I like how you post all of this yet don't even know the basics of gasses being fluids.
1: that pressure reduction value weights 10x more than the motor itself. A reed valve sets a minimum pressure not a max. How would that work? TATA discovered that the air in India was too dirty and clogged the compressed air engine. !!
@@stephencaparelli7733 I felt so smart when he said that! Maybe I can be an aeronautical engineer after all! But in actuality, I work at IKEA, and yeah, no.
Use less diameter bearings to reduce the area of leakage in them. Also, it's better to have more volume of the engine cuz it improves the ratio volume/leakage.
Sealed bearings should also help
I believe if you have more volume in the engine the running time will lower because air in the bottle is still the same so % of air that is wasted is higher
Also smaller bearing makes it lighter. Higher chance that it flies.
Or 0 ball bearings, since it only runs for a couple minutes he could just use teflon sleeve bearings/bushings with some light oil or grease. Also if he was to change the drive shaft to steel he could use a much smaller diameter which would result in lower leakage around the output.
@@balrog240Sealed bearings would have much more resistance too
As an engineer I've seen something similar in a marine application here's what I suggest. Use a 4° reverse vein use your pushrod design. Use graphite powder dry for a lubricant and gap filler. Your central peace should be two parts to clamshell against the veins and the pushrod unless you can get tight fitting as single piece. You may even be able to go to a three vein 2° reverse angle using a cam style to move the pins in a direction to keep the veins close to the outer shell. And you could then use a nitrite seal or similar automotive style seal on the output shafts of your rotary vein. That would minimize your parts your escape portions if you do the tight tolerance thing again with the seal it would keep everything much tighter with less friction minimizing your parts and less air gap
This guy is probably gonna win :/
Hi Integza, Phi here!
I have a bit of experience with vane motors and vacuums pumps. It looks to me like you can solve a bit of your tolerance problems by making your rotor larger, and the vanes shorter, in your flappy motor design. It will give them less opportunity to flex under the air pressure, and allow for you to run it faster or at least more efficiently. For the vane design on the other, narrower vanes are better, but the cavities should be sized such that there are extremely tight tolerances, and when the vane is fully extended there should be about 2/3 of the vane left in the gland, otherwise friction will try to drag it out of its space, causing more friction, and eventually self destruction.
Gaskets and rotary shaft seals are grand!!!
Three vanes are better than two in all regards.
Cheers!!!
Stanton fans here
Stanton's pretty cool
so obscure!!
Don’t watch him that much but when I do he cookin
Could not believe he opened with Tom smack talk..
and D4A
This is awesome. I love this little flappy engine; I think you have landed on what could be the new gold standard design.
Please check the sealing on the piston's axial direction. If you machine annular flap seals into both piston faces, remember that the propeller is pulling the piston towards the front, so the seals on the back face of the piston will have more clearance.
For even better sealing and less friction, you could make the entire expansion chamber PTFE, using the resin housing for structural support. Or just machine a grove in the housings for PTFE o-rings.
Finally, your bearing isn't the best one for an airplane. You need a thrust bearing in the front of the engine and a sealed bearing on the rear. The front bearing and engine housing is taking all the load of pulling the airplane forward.
Nice use of a compliant mechanism,
It might be nice in a pump too
@@orestdubay6508 Yep my 50 year old marine engine used a vane cooling-water pump with "compliant" rubber impeller, It's a far older design than you think. Making it low friction is the challenge here though.
Given the friction, what about making the flaps replaceable tabs that lock in with a key fit, but doesn’t add extra leaks? After enough run time the flaps would wear down like apex seals do.
My favourite video of yours. It's just one good idea after the other.
Quickest/easiest fixes:
1. 3D-printed flap mechanism + teflon housing. CNC cutouts around flaps increase the volume of air wasted. Maximize pressure differential vs volume per compartment.
2. Print versions with different amounts of flaps. Finding the correct amount in theory will take forever. Just print versions with 2 up to 5(?) flaps and see what's most efficient. No math needed.
3. Use a liquid, plastic-compliant lubricant. It's basically a free sealing agent.
4. Ball bearing in the center really makes air leakage too easy. Teflon center shaft and a lubed bushing would have just as little friction and be much easier to seal.
5. The front and back wall need to keep the air in the flap compartments. Look up a "labyrinth seal". Perfect for rotating designs, easy to implement, basically zero friction. Add the lubricant, boom, got a great seal.
6. Where is your outlet? It wasn't entirely clear in the video. Just make sure the air escapes quickly after the halfway point, otherwise the engine is working against itself.
7. Housing with a nautilus shell shape, but with a very smooth transition, so it doesn't wreck the flaps or cause them to catch. Then you can use almost the full rotation for expansion. Adjust outlet position accordingly.
8. Make sure the back wall is stiff enough to make the deformation due to axial force from the prop negligible. Otherwise sealing the flaps will be even harder.
9. Ideal energy extraction: You're extracting elastic energy from the air pressure. Once the air pressure inside the compartments is at zero relative to the atmosphere, you've taken all the energy out and can reset using the exhaust. If you're starting out at 2 bar, that means you're at 3 bar relative to a vacuum. If the volume then triples between input and exhaust, you'll be at 1 bar relative to vacuum and 0 bar relative to atmosphere. There's your formula. Rocket nozzles work on a similar principle.
Those are all the easy ones.
Good luck kicking Tom Stanton's 🍅
(Both of your channels are great, but trash talk makes the challenge fun.)
The little flappy flaps are an excellent addition! I'm also really happy to see you finally put a regulator in the system! You saw immediately how much more consistently the engine ran.
I now want to see what happens when you add more of them - 3, 5 or 7 vanes.
Most fans use an odd number of blades to help reduce vibration, but I think a higher number of blades will give you better static pressure, and drive the prop better.
make the engine housing from another material that is harder and lubricate it with graphite
powdery graphites are gonna stick in bearing lubricant and can slower them down
The advantage of oil is that it also works as a sealant.
@ojaswiagarwal-x1y 2rs bearings after time will not slower an engine
@@FedericoLucchi who said u cant have graphite and oil? i remember some old car oil had graphite in it
@dominikvarholik7519 zink.
Hello, in order to reduce leaks between the transparent plate and the rotor, you could install a series of 2 or 3 baffles, they are used in applications with very high rotation speed and high pressure. I remember this passage from my engineering classes. With the tolerances of your printer this might be possible. (sorry my english is bad it's not my native language)
Edit : There is no friction with this solution, because the two parts do not touch.
I was thinking some matched up oil grooves for the same leakage points. since it's a short duration doesn't matter much but needs sealed.
and a frigging o ring around the main body and clear plate. once the spinny bits are better sealed, that body is going to be the next spot.
I also thought he should try to stop that "3D" leakage. Perhaps the transparent plate (and rotor) shouldn't be flat.
No your english is not bad
@@Noksus thanks 😅
Given the leakage occurs through the bearing, the bearing itself could be extracted from the main piece. It would be kept aligned to the rotation center axis, but only sustaining a center rod with minimal radius to be sealed against the pressure chamber.
1 Upgrade to high-quality sealing materials like silicone or rubber to keep air from leaking.
2: Redesign the valve system using CAD software to ensure smoother air flow and efficient operation.
3: Use the Teflon rotor directly as a bushing, eliminating the need for bulky bearings.
4: Adjust the exhaust port design in your 3D modeling software to better match the angle of the vanes.
5: Incorporate heat-resistant filament materials, like ABS or nylon, during the 3D printing process.
6: Integrate noise-dampening materials, such as foam or silicone, into the motor housing.
7: Choose durable filaments like PETG or carbon fiber-infused for 3D printing to withstand pressure.
8: Calibrate your 3D printer to achieve precise layer bonding and avoid defects.
9: Post-process printed parts by sanding or using a chemical smoothing agent to reduce friction.
10: Design parts in a modular fashion, making them easy to replace or upgrade in your CAD software.
these are sum ways you could do this i guess
Your little flappy air engine is genius! I like the fact that Tom has inspired you. There's so many good ideas and input from the comments.
I LOVE LOVE LOVE that you took on this challenge.
The pneumatic engine removes combustion dangers, allowing everyone to try new ideas on one of the most useful components of the modern world.
Converting stored energy into mechanical rotational energy.
Years could be spent tinkering with pneumatic engine designs. Its incredible the varied possibilities that exist, things that have never been thought up just waiting to be discovered.
My favorite video EVER that you've created.
Except needs more exploding "Tom"atoes.
Or you could just look at a Wankel
A way to eliminate some of the leakage as seen at 12:40 can be using sealed/shielded ball bearings or even better, fluid shield bearings! not only it'll eliminate the bearing leaks, it'll help the engine run smoother since the bearings are constantly lubricated.
There is nothing sacred to him.... everything is a rocket for him
Since the flappy engine has so much less friction, have you considered going back to a three vane or four vane, that way more of the pressure that’s coming in has a smaller expansion area before the next vane kicks in, I may not be explaining this correctly but a third or fourth vane should give it more torque and or speed, just note this is an idea before the end of the video, timestamp is 18:37…never mind I just realized the total length of the video😂
Also trash the bearings, instead make the rotor with the “shaft” built in and in the main block just have a blind hole and do the same on the front cap. That drops the leak area plus with it being made from PTFE, shouldn’t be much friction!!! {-o-} diagram for example!! Love your channel, and Tomatoes are totally gross!
i think more Teflon wouldn't hurt and for an idea it would be really cool to see you mount this to a car or a turbine
and lose the weight use glue and rubber fitings
The connected vains idea was a display of ingenuity.
wait for the flappy things
vanes
That confused me... I'm not understanding how they were both always in contact with the outer cylinder, when they were spinning in an offset radius; was there a spring in that shaft?
@@userzero9259 it doesn't matter that it was offset, all the matters was that they stay the same distance. if you're good at visualizing, imagine focusing on just the rod. it doesn't matter what else is rotating around it, it's just getting pushed back and forth from the pivot's POV
I LOVE the childlike naiveness of youtube comment section. It's not like pneumatic engines have been practically solved for years if not decades and literally anything seen in this video isn't new nor unkown to the content creator beforehand.
He's not even that good at pretending coming up with new solutions or being surprised at things like..... not using any lubricant, LMAO.
Can u try to make a tesla turbine with this method?Nice video i love it!!!
I think the torque would be too low especially at the start. 😢
The whole point of a tesla turbine is to blow air directly on a set of discs, so unless you mean "scrap everything you were doing to make a Tesla Turbine instead", the mechanism he's using inside is taking up the exact spot he needs to make a turbine with.
Quick, simple, and requiring no major container changes: Increase the number of flaps. I KNOW you reduced the VANES to 2 to reduce leakage; however, flaps are different because the pressure increases the seal. Thus, more vanes means more torque AND without sacrificng sealing. NOTE: I am NOT suggesting going from 2 to 3; rather I AM suggesting seeking a sweet spot which might be 3,4,5, etc. to find the optimum between the net increase in friction with the net decrease in leakage. You MAY need to simultaneously seek a sweet spot with regard to pressure as well. Hope this helps. BTW, I love your presentation style.
i think it very much depends on how much friction each vane/flap causes, if there are two pressurised cavities (implying 3 vanes/flaps under some pressure) then the mid vane has pressure on both sides, albeit that the pressure in the cavity nearer the inlet ought to be greater than the cavity about to exhaust.
It's not that simple. If you have too many the airflow into the chamber gets cut off too soon. Most energy is probably extracted between 30 and 60 degrees after the inlet. With two flaps the movement after 60 is not helping much. With four or more you are not maintaining full supply pressure throughout the productive part of the cycle. It could be calculated more rigorously but my gut feeling is that 3 may be the optimum. You are right, his reason for moving to 2 has gone, he need more flaps.
@@nomdefamille4807 Thank you for your well considered response. In my mind I pictured sort of a water wheel -- but you may well be correct. I am not much of an engineer; I have always taken the million monkeys approach -- admittedly, more tortoise than hare; but it usually works in the end.😀
@@nomdefamille4807 Thank you for your insight. You are obviously a much better engineer than old kitchen chemist me. I had visions of a sort of water wheel efffect; but, that just might be the amateur in me. I still think something along those lines might be worth a shot. Who knows; even if it fails, it just might provide some iterative inspiration. 😀
@@tuberroot1112 FYI Commercial vane motors can have up to 10 vanes. It appears to be a judgement about lower friction vs lower internal leakage and RPM. As long as the vane still has space to expand outwards then the air can continue to expand. Given the inner rotor is offset from the outer, the rotor can rotate 180º and continue to expand.
What a great take on building and improving a pneumatic engine.
I am no engineer, but here are some improvement ideas:
- Reduce the overall weight of the rotor and the thickness of the wings to reduce the friction
- Reduce the leakage between the rotor and the case, maybe with some gasket or sealant. Maybe a graphite or carbon based lubrificant?
- Consider tweaking the area of the chamber versus the area of the wing, there must be an ideal ratio to improve efficiency
- Change the shape of the wing to a "C" shape in order to optimize trust, like a water turbine
Awesome video (as always), cant wait for part 2.
Keep up the good work
Best regards from Évora ;)
Seal the bearing, use a high performance ceramic bearing, 3d-printed bolts for lighter weight, create a turbo charger for the engine. Like a rotary engine, use a center block housing essentially using two engines and combining them into one. (Dual rotor). But the simple answer is to hollow out the circle piece under the flaps to allow more air underneath the flaps and more air to fill the gap creating more power, this also lowers the weight significantly. If you make a dual rotor style design, to solve this offset in the engine, offset each block opposite to the last to balance it out.
More, longer, thinner flaps.
On the exhaust side, you need to make it easier for the air to escape.
Fill it with graphit powder as lubricant one time.
Yep, a dry lubricant would be beneficial, though I would go with molybdenum disulphide.
Yeah he went dual veins because of sealing and springs and kept it as he went to flaps but with the flap designs there is no reason to keep only two veins. Not sure if more veins will help getting better results but it should be tested for sure.
@@gg4760-k5n Three vanes will probably help, because as-is air inflow can leak over the back of the rotor to reach the exhaust and lose pressure. Three sections will allow a filling section, a power section, and an exhausting section.
would graphite powder help when he's made the entire rotating assembly in PTFE/teflon though?
I fully agree with the bigger exhaust though
more longer, thinner flaps makes for turbine, but that'd be heavier and brittle - engine that works till first touchdown? 2. Do we really need to sal friction of teflon against teflon? Doubt.
THE LEGEND HAS UPLOADED ONCE AGAIN!
Yeah, I was starting to get worried about him.
3:50 your bearing don't rotate
add a ball valve before injection, reduce chamber size, make a spiral to open and close the ball valve only when you need it for the amount of air needed to achieve the rotation you need.
Issues to correct if you want to use this in a plane:
1.In the engine where thee air get in make it a little thin and set pressure to 3 bars. (so it works like a water jet cutter, generating more thrust)
2.Optional:- Use silicon glue to fix leaks
3.If you can try a 4 vane engine
If you also put the flappy flap on the side the engine would have an even better seal.
Also, test again with 3 or more flapy's at a lower pressure. Maybe you can increase the runtime even longer.
you should make the exhaust port bigger so the engine has less resistance while pushing the exhaust gasses out
As an engineering educator, this is shuch a great video: how to design in Engineering. Thanks.
Add a casing around the motor and connect the intake to the space between the motor and the casing. This space will then be pressurized, preventing air from leaking out of the motor. It is particularly important to ensure that the shaft penetration is properly sealed.
You'd still have to seal around the bearing and the rotor so the intake chamber doesn't leak into the exhausting chamber.
HEAVY!!!
That is absolutely brilliant. Your engine might be more efficient with 3 vanes or a side inlet valve to allow the compressed air to uncompress in the chamber before being expelled. I have another suggestion. Instead of running the compressed air engine using a bulky soda bottle filled with compressed air, try running it with a dry ice battery. This is small pressure container with some dry ice in it. As the dry ice evaporates and releases CO2 gas it cools the container, which reduces the pressure in the container. To maintain the desired pressure a tiny fan blows air onto the container to raise the temperature of the container. So the speed of the tiny fan regulates the pressure and power output from the battery. 100g of dry ice releases 54 liters of CO2 gas.
To improve this wonderful tiny thing:
1. Center the air intake as much as possible for the airflow to hit the flaps (it's not about max torque, but about the air efficiently pushing them)
2. Make the flaps into a pelton turbine shape: if it's efficient for water, it's probably great for air too!
3. Get a bearing with a rubber side: a lot of pain was leaking through the bearing!
4. as @naasking was saying, experiment with 3-flap design and try to reduce back pressure
5. find the optimal width: with eiter software or a couple of prototypes, surely there is an optimal width that maximizes torque without killing rpm.
I hope this helps! Much love from Italy!
the traditional pelton wheel gets its advantage over the venerable water wheel by providing a course for the fluid to reverse direction in to an "unconfined space", so for that aspect the air needs to leak out. here i think he needs the torque of the "rotary piston". if he is currently running for 3 minutes against a need for 2 then he could open up the inlet nozzle slightly and increase the depth of the rotor/ motor. he really should try and dump the regulator, the assembly would better use the stored energy if it could withstand peak soda bottle pressure. and in terms of flight performance anything to reduce weight, as all others have pointed out.
@@nomdefamille4807 great point
The engine doesn't work because of airflow, it's the pressure differential of the air expanding inside the chamber that causes it to rotate.
@@NeilStansbury And what is an airflow/wind if not a pressure difference, you 'genius'?
@@dziubo1 I suggest you go and have a conversation with Mr Bernoulli and ask him to explain his gas principle to you, then you might be able to answer your own question.
3D print a seal on the ball bearing, similar to a sealed bearing (or try a sealed bearing?). I suspect that reducing this source of air leakage will help. Also try adding oil into the chamber before you screw on the cover, instead of just pouring oil through the bearing. This oil may help take up some of the tolerances.
Apply 2bar pressure INTO the bearing, through the ball cage and chanel the air to chamber/s. Used air exhaust opposite side to atmosphere.
Please make a version 2 of your turbo jet engine that will run for longer , it was one of ur best videos, I too felt the joy when it started working , plsss.
that was one hell of a thing
Yaa I felt the excitement too😉
UP
Make the rest of the shell out of Teflon, possibly use a Teflon bushing to seal the output axle to the assemble face to prevent air leakage from the bearing which also drains the lube quickly.
A couple of things that should help.
1. Switch to smaller sealed bearings over the open face you are using. If you take the seal disk out of the bearings wash them out and repack with a thin and I do mean thin PTFE grease. 2. When machining leave as much material in the hub. The voids you have made in the hub are pressure vessels as they go from high pressure to low pressure you're losing efficiency and air volume. To minimize surface friction where you have through holes just make a small depression half a millimeter deep so you create a smaller pressure vessel and cut down on surface friction area. 3. Use smaller diameter end mills when cutting your flat veins so the volume of material removed is smaller therefore cutting down the static displacement of the chambers.
Can't wait for Tom to make a new one, and this to turn into some mad competition
Hey there! I just watched your latest video on the compressed air engine, and I have a few thoughts and suggestions. First off, you removed one vane, leaving only two, and replaced them with those floppy things. Remember, as you mentioned before, more vanes generally mean higher RPM and power. So, have you considered adding more floppy things instead? Speaking of improvements, why not try lubricating the engine with graphite? It worked well for the rotary engine in your previous video, so it might be worth a shot here too. During the leakage test, I couldn't help but notice some noticeable leakage around the bearings. That might be something to look into. I'm a bit curious about your end goal here. If you're aiming for maximum flight time, the two-bar setup might be sufficient. However, if I were in your shoes, I'd consider increasing the pressure up to 2.5 bar for better power output. Lastly, when you eventually get this contraption airborne, I wonder if the pressure regulator might be too heavy for successful lift-off. Have you considered its weight impact?
Keep up the fascinating work! I'm looking forward to seeing how this project develops.👍
I totally agree 👍
At least rewrite in your own words what the AI outputs my man
Yeah I know, but I'm not English. I'm just shit at writing in English. It's also not necessary I mean no one will ever read this besides you. So yeah the translator does the thing for me.
If you keep if named flappy valve it should probably resemble flappy bird!
Could you replace the vane system with a compliant mechanism?
For optimization:
I think you can change the expansion chamber to be more round and have a better flow profile. Second, you could adjust the volume of the expansion chamber. Third, adjust the amount of flaps. Optimizing these could produce a higher rpm and longer run time.
The flappy engine is a brilliant idea. Could you make teflon bushings to replace the bearings, as that should stop a lot of leakage out the side.
Now that you have eliminated the veins, you could lighten the rotating mass by drilling/milling holes in in a bolt circle around the bearing without compromising the integrity.
Your videos are so good. Thank you.
Could you use magnets to connect the rotor and propeller? You'd eliminate the bearing leaks, and the additional weight may act as a flywheel
Nice idea! Have a back half and a front half. Front half would just be a front bearing and crankshaft to the propeller. Connect the two rotating parts via magnets. The issue would be you'ld want strong enough magnets to keep the parts connected but not so strong they tried to clamp together causing friction.
I want to say no, that won't work but I can't think of any reason it wouldn't that couldn't be overcome with some clever design. At least for very low power applications like this. Yeah, I can think of several things that would prevent the motor working but they are all things that could be solved easily. Nice idea.
The Flappy Engine has to be one of the most technical names ive ever heard.
Another name for it could be a Floppy Drive 😅
18:45 Hero's engine is truly awesome, so is yours!
If you go back to vanes, using more vanes would reduce the leakage area. You could use the opposing bar in a cross configuration for 4. Use cylinders at the tips to seal against the wall. If you cut ratchet type notches in the cylinders, you could use the air trying to leak to push the vanes harder
Love seeing compliant mechanisms. I wonder if the outer housing could be more optimal if it isn't round, to maximize the force applied to rotation over leakage.
Maybe you could try graphite powder to coat the internals, which would also reduce the friction, It would be like having oil but completely dry.
I thought graphite was slightly abrasive?
You should check out the Di Pietro Rotary Air Engine. It operates on a principle similar to the pneumatic vane motor, with greater efficiency but can be harder to manufacture,
It's an inverted vain engine like liquid piston design for Wankel, interesting
This video was one of the best you did this year. I feel like a lot of times you only try a few prototypes and then end it, but in this one you kept trying and trying and making adjustments and more prototypes and it was such a great journey!
I would love more videos about air engines.
To make it better: use your flappy seal design to make seals against the front and back ends between the rotor and the wall. Also, build your own lightweight pressure regulator. It might not actually put out more power, but you can make it lightweight so that it could actually fly.
You should make an radial lip seal that closes in the axial direction towards the bearing as part of the front of the transparent housing behind the bearing. Or an axial shaft seal. .
Or just fit a regular old oil seal there like all vane motors have had for the last 100 years or so.
oooo an engine that works via compliant mechanisms, that's fun!
Biggest issue I see is that you probably have quite a bit of wear on this engine, even with such a low coefficient of friction, right? As long as it runs, it runs great, but eventually the pieces will wear down so much, you get too much leakage again, I think.
With the flexure version you *could* try going for a three-finned variant again. Might be even better? Though two-finned seems to work rather well
To increase durability, you can make the flaps longer.
Right now it looks like they are just about the ideal length for maximum leverage without leaks, but when they wear down it will very quickly start leaking since the flaps won't reach the edge anymore.
So for a more long term engine, I would add maybe 2mm of length, slightly decreases efficiency but makes it much more reliable over time.
i mean, why stop at three finns? as i understood it, the more the better
by making the flaps longer you gain a certain amount of built-in wear resistance
the flaps may wear down, but they have to grind through the whole extra length of the flap....
longer flaps means mroe durability, but also more friction, right?
@@Kram1032 as long as they aren't so long that the cross section of material touching the wall increases, it shouldn't be much more.
however, if the flap is too long or thin then then it will overcome the strength of the teflon, sag and drag excessively along the wall
You can try with different propellors with other sizes and angles as the optimum propeller is different for each type of engine.
One of the nice things about Tom's was it could be made at home simply with a basic 3d printer and not require much extra machining work.
But it is nice to see that the step up from his to yours really isn't out of the question for someone with a bit mre tooling availible.
Combine it with some kind of expanding gas, burning something to get the pressure. It will last much longer 👍
Finally, another upload from you!
Vent the exhaust into a second (smaller) motor of the same type to more efficiently use all of the air pressure. To make a better seal against the top and bottom of the motor, use a rounded surface on the top and bottom of the main rotor and sand a concave divot using the the rotor in the same way you explained in the video and use bearings that have ceramic or gem balls along with a seal over the race.
I don't think you need a second turbine.
If theres a 2 bar input, you just need to make sure that the chamber doubles in size in between the input closing and the output opening.
Yes if you were working at very high pressure, where this wouldn't be practical, make it double or triple expansion.
I also wonder if an air bearing would be better in this situation.
When I buy any 'cheap' air tool, I run it for a baseline, then tear it down and check everything using a granite surface plate and Prussian Blue. Once all the parts fit, lapped, sharp edges chamfered, orientations to ports corrected, that cheap $20 tool will almost always perform like an expensive brand name tool. Love your flappy design and your follower vane, I can see real world applications in my future.
shh that's the secret dont tell anyone
1 - Make the central shaft out teflon and lap it to a free spinning fit with the housing to eliminate the bearing.
2 - Use 2 very thin teflon washers that are recessed into the housings on either side of the piston and have an interference fit with the drive shaft. They provide a bearing surface, seal, and any bypass ends up being used like a Tesla turbine.
3 - Print the piston out of the most flexible material you can with a small cavity in the ends of the flaps to insert a small bit of teflon. By 3D printing you make the chamber size smaller for higher torque. Flexible material suggested for longevity. I'd probably go with a long triangle of teflon for the insert to provide the smallest friction on the wall of the housing as well as creating a pressure seal on the flap socket.
I agree with others that more flaps would be a good idea. I'm thinking 3 or maybe 4.
I would be really interested to see the entire engine changed to a Tesla turbine with the exhaust port coming out of the rear of the drive shaft to scavenge that tiny bit of extra thrust. Though I guess any pneumatic motor could be ported for a similar effect.
One thing I could suggest is giving the flaps tension against the housing. If you want to nit-pick; then there's going to be a resonance frequency for the bump/rebound of the flaps in which you'll hit optimal seal at a specific RPM. I would also test having a third flap, and if you hadn't already, slotting the exhaust along the entire recoil arch.
you could probably get more rpm if you added a few more flaps and measure at what point the amount of friction from more flaps decreases the efficiency. Great idea though and beautifull you made it work.
For many years now I've been thinking about the ultimate air compressor with no moving parts. It would involve several pulsejet engines, long enough so that they would transform the deflagration into a detonation wave, acting as supersonic PDEs (pulse detonation engines) distributed radially in a star configuration, or parallel to one another like the chambers of a revolv*r cylinder, facing a pressure tank. They would repeatedly fire one after the other in a circular pattern sequence, a bit like a Gatling but with no physical rotation, maintaining the high pressure inside the tank, which could be used to feed the nozzle a Coandă disc aka Aerodina Lenticulară (but this one his another story…). Indeed, the equations of fluid mechanics have two parts: velocity and pressure. For the past century, the various successive engines developed have favored the exhaust velocity over gas pressure. But the very first engine, the pulsejet, did exactly the opposite: it imparted a lot of pressure to the exhaust gas, and relatively little velocity. The high pressure of the pulsejet engine, and more exactly its modern iteration the PDE, could be leveraged to impart a great pressure into a tank, with no moving parts (or maybe just servoflaps either electronically or better mechanically controlled) with a very good power/weight ratio. If only I had a 3D printer to build the prototype!
What about combining rocket engine and compressed air engine. For example, making a system that produces giant amount of reserve gas that could power the engine for a long time with relatively small mass. See, you can only pump so much air into two bottles, but storing potential gas in solid form, in my opinion, is a very interesting idea. I am thinking a slow burning solid state rocket motor that does not produce thrust, but rather accumulates and compresses exhaust gases?
VERY HEAVY solution... no way any twin engine will be more efficient than single chamber one
The flaps could be made more robust as a pivoting hinge (it would probably introduce another leakage point, but might be worth a try). The hinge would just be a cylinder embedded in the circle. From the top, the hinge would look like a comma, with the circle part of the comma inserted into a corresponding round cavity in the rotating circle.
You should look into how sealing forces work in a vane motor. Basically, the fit of the vane in the rotor is not important since the air pressure will force the vane to one side of the slot (and out towards the housing). The end play of the vane in the housing is very important, on the other hand, as a gap there provides a straight leakage path to atmosphere with no inherent sealing forces to counteract it. Also, the vane should sit deeper in the rotor, the length inside the rotor should at least be greater than the length outside of it with the vane fully extended. This will both reduce friction from the vane tipping over and eliminate the need for springs. In the end, your choice of a compliant mechanism eliminates all of these aspects except for the end play which must be carefully controlled.
I wonder, do you eat pizza without sauce?
if he's anything like my brother-in-law, who's also lifelong repulsed by tomatoes, then no - sauce is fine, it's really just the texture of raw tomatoes that scratches their nerves.
Interesting - I love both
@@KerbalFacile For my daughter, it's the slimy shit that holds the seeds. everything made from it is fair game, though.
you van make the enclosure toroidal and the flaps conical.
To help with sealing like how the valves in a conventional engine work?
1. You can try to change inner diameter to find a sweet spot for friction forces vs air waste rate, to find a better energy efficiency.
2. Add silicon grease inside (not a spray)
Put in another intake valve next to the one you have. Take a tube and feed the exhaust from the motor back into the cylinder at the new intake. Re use some of the compressed air for a longer run time
this will not work the air just moves allwais from Higher to lower presure areas
combining some ideas here: 4 vanes with two rods for balance reasons, engine is pulsing with only 2, one rod higher than the other so there is room for clearance for x shape without intersection. reduce weight by replacing bolts with something lighter, maybe bolts made from same material as housing, or weld with epoxy, grease the bearings ofc but usue something viscous because that will help reduce leaks a tiny bit, see if you can reduce weight on the chassis somehow, maybe a thinner teflon layer and a composite outer layer glued together with epoxy for weight reduction, try removing the shaft instead making the shaft and crank assembly a solid piece. make tolerances tight and run it with the abrasive until it becomes self compliant.
1. you could reduce the radius of the blades, that could save some weight.
2. point the exhaust backwards or down to gain extra thrust
3. increase to 3 or 4 'flaps' to catch more air
4:41 You timed it without any back pressure. Once it has a prop on it, the motor will run slower, increasing the running time. You can use a bigger nozzle.
It's just a standard air tool motor. Your seals are two wide at the head, this creates friction. You also need to oil it through the air inlet port, this will help with sealing. You need to use a high quality sealed bearing. They usually use phenolic sheet for the vanes. The rear edge of the vanes are shaped in such a way that it helps the other edge seal against the bore face.
i love the idea , 2improvments i would make is 1. an exit tube to take the extra pressure and put by inlet with a pressurized T 2. when it starts generating to much pressure it would deliver the over pressure valve making it go back to the air bottle allowing more pressure and more air to make it last longer.
Hello, these are some of the improvements i think you can make...
1. The method you used to obtain a perfect fit to reduce the air leakages, you can use the same method for other parts.
2. Increase the no of flaps to 4-5. I think 3 flaps will be the best.
3. You can have multiples inputs (all of the same pressure). no of flaps = no of inputs
Thats all I have to say.This is an incredible build.
HUGE FAN OF YOUR WORKS INTEGZA❤ WATCHED ALL OF YOUR VIDEOS AND HPOE TO SEE SOME MORE JET ENGINES😊
For the plate leak on the face and back of the engine, you could hollow out the center of the teflon vane rotor and place a trough.
I don't remember specifically how it works but very small troughs that are like deeper REALLY reduce leakage and it would REALLY lower friction on the face and back.
also if you want it to fly you'll need to reduce weight but any number of things can do that
You forgot to include colored fluid leak test footage.
For upgrades I suggest:
1) put thin, bit oversized rubbery sheet on the flexvane to form lip seal, or copy the process of making lip seal from Tom,
2) seal the rotor - either between rotor and sideplates or shaft and hole in sideplate - I think Viton xring would be best but NBR oring should do or do lip seal again,
3) lube everything, but not excessively and check material compatibility just so parts won't start degrading
4) do a long run test to improve living hinge design of - it may be subject to fatigue failure,
5) add more vanes for smoother opeartion, though I don't know how that influence efficiency,
6) check if position of outlet is correct - I have the impression that waste air is compressed a little,
7) noncircular chamber to lenghten expansion angle; current design is at 180°.
More vanes more power. More efficent use of energy. What is amazing about your flap idea is you can have many more.
Try putting the flaps at an angle.
Also using a softer material for the vanes than the casing is advised. So it whittles em down sealing a gap. Think how a brushless motor works.
Then design the flaps to still make perfect contact while they whittle down over time.
To improve performance and reduce weight:
1) Use carbon fiber for the housing to cut down on mass
2) Add precision rotor seals to minimize air leaks and boost efficiency
3) Experiment with a hollow rotor design to reduce inertia without sacrificing strength. Imagine how much faster and more efficient it could be!
Also Maybe you could do a collaboration with tom Stanton to improve this engine more and Maybe build the best air engine in the world
The biggest leaks near the end seemed to be leaks between the planar surfaces, or to put it another way. The air seemed to leak between the rotor and the clear surface on the front.
If you make the rotor slightly wider than the side walls, add the abrasive, and then spin it with those being pressed together you can probably achieve a better fit.
You could try to increase the area of the flaps relative to the leaking e.g. by increasing the depth of your motor.
And to harvest more from the power stored in the bottle you could ditch the pressure regulator (essentially throwing away a lot of stored energy) and add a motor, which can be switched from series to parallel pressure.
Make the full housing air tight (including the bearings).
Hope that helps.
The leaks occur mainly at the ends of the rotor. A longer rotor will have a higher ratio of vane surface area to leak area. You could also use labyrinth seals between the faceplate and the rotor to reduce leakage without increasing friction.
Yay!! Missed you Hermano! Always made sure to check your channel to make sure I wasn't missing out! One day I will be able to do some 3D printing as well!!
Ideas
1: Make a 3D printed water turbine for small creeks and streams. That would get you out of the house and help people in rural/poor areas create some power!
2. Make 3D printed outdoor sensors!
A. Tree\plant growth monitors
B. Soil Moisture content
C. Wind Speed/Pressure
D. Soil/Air Temp
E. Insect detectors/counters
F. Spore Detectors
*Make them self sufficient and with drone beacons to direct drones to water/spray insecticide/fungicide on the plants!
Let's discuss improvements: 1) go with a spherical rotor rather than disk rotor, 2) use a lifter valve to control outflow, 3) use trapped flaps or valves (a trapped valve is one which is framed with guides to either side. Hard to do on a disk style rotor, but on a spherical rotor, the points of the sphere merging to the shaft can have guides placed to oiled channels within the chamber, which act as permanent wings. The valves extend down between the edges of the frame, ensuring smoot movement and proper contact to the chamber wall). 4) Stepped chamber contact. The wall of the chamber should be contoured to the valves and the rotor. (Be it a disk or sphere). Even if you do continue with a disk rotor as you have done in this video, the valve and wall should meet each other at a contoured position. This improves contact stability at higher RPMs. 5) Nanoscale plaining: while you likely can't achieve this at home, if you were to design and print parts from your friends who print with the nano-porous stainless steel, you could achieve far higher tolerances thus improving efficiency. 6) Use contained magneto bearings.
Disk vs Sphere vs Cylinder design.
Efficiency and stability are key, and one of the biggest issues with your design is stability, with a great deal of leakage. The valves you have aren't sealed within the disk, and the disk is too close to the bearing to prevent major leakage. As you demonstrated when you use the component to component grinding method to refine the gaps, too much pressure can build up causing the engine to break.
Using either a sphere or cylinder that is longer than your disk design could resolve these issues. For example, you can create a buffer zone with both the cylinder and sphere to reduce pressure on the bearing and drive shaft while improving internal leakage. The extra length of both gives you wiggle room to adjust pressure controls.
My final thought is simply to switch to a magnetic bearing system, and isolate the drive shaft from the internal workings of the rotor. This should work even with your disk style rotor.
Use neodymium magnets in opposition to create a magnetic suspension for the rotor on both sides at the appropriate position within the chamber (the offset position). These magnets can be situated to not only act as the bearing for rotational movement, but as side to side movement (jitter). On the end that will attach to the propeller, use a normal bearing to anchor the propeller and driveshaft, and then use magnets attached to your rotor and an external disk connected to the drive shaft of the propeller. In this way the propeller will not be damaged or ejected incase of blow out, and the rotor can spin faster than the propeller while driving it. (Magneto induced rotation is used in water proof applications all the time, including power generators). By using magneto bearings and a magnetic drive system, you can eliminate all external leaks and control air outflow as specifically as you want.
To maximize the efficiency, you should try to maximize the pressure difference between the injected air, and the exhaust air. (i) Put the rotor axis closer to the edge, i.e. make it more eccentric, (ii) make sure the air starts injecting at the moment when the cavity between the flaps is the smallest, and exhaust opens up when it is the biggest (this depends on the number of flaps you have), (iii) add more flaps (this comes with a friction drawback tho). All this assuming you work with high pressure, if the pressure is low, make sure there is no less than 1 bar at the exhaust.
To get rid of the Heavy screws that make the plane harder to fly: try to use some glue. This would also prevent leakage to the outside. Since the walls of this are thick too, you should try to make them thinner to lose weight. When using bottles, the bottle should be as near to the engine as possible in order to make the airflow faster and the way air has to travel shorter, reducing friction and loss of pressure. And the easiest way of making a bottle last longer is increasing its size, say to 1.5 litres. Bottles of this size don’t weigh much more but can store more air. Using a ring of rubber in the area between two parts can also decrease leakage
Hey Integza, I figured I'd throw my hat in the ring after I gave some improvement ideas I had for a rotary vane engine to driving for answers on my how a 3d printed engine (about 3hours something in) caused a dwarf planet to hit us. But suffice it to say the sides are your biggest issue, you're studying in school I'm sure you already know that. Same thing for how friction in the system is just ridiculous thanks to needing a sealing material that is constantly rubbing at different pressures and velocities.
How does the air come out!!!!!!
So! The easiest way would be to make a oil bearing that uses sliding linear bearing towards a center that allows for a crank gear axel to rotate. That's the layman's explanation. Oil on the inside diameter of the housing with a circular grove cut in to the side to have a type of 2 piece "mushroom" bearing area would work best for this design. Or even a flat circle that uses T cut sides to have the plastic (or metal) forced into oil that has to go around multiple right angles really increases the seal. A few offsets air channels allows for the oil to be separated during the airflow into the intake, like an oil catch can. With a few rings on either side of the housing this fixes your leak issues & the vane movement issues. Mostly, nothing is perfect, some oil will get lost & as such it wont be perfect. The ring that is the bearing just needs some holes and threading to allow for the plunger based axel, like you were using in this video, to self align. However!!!!! Using a vacuum would help you have it transfer faster, but that's more difficult so instead a fluid that is lubricative is usually going to be better. Some small o-rings technically work, but they are prone to degradation, so a simpler system of oil traps that squeeze the oil through holes in the spokes would work better.
Several tubes basically with some small holes, like you drilled on the video, will work placed in a larger tube that are the spoke housing with help keep it sealed using old school 2 stroke engine tech.
Here's how the air comes out.
The air has to come out through change of the 2 stroke engine hole placement on the outside spokes. It slides down enough to expose holes that lead to the housing area that has the spokes poking out and sliding around in the in-between area of the 2 halves of the housing. That allows for you to put a manifold around it to use as a scavenge (Bernoulli's principle here) effect for flowing air to help with air coming out to further increase efficiency. As the spokes poking out can now help "seal" a little (not much its mostly to create a type of flowing directional air to aid in this effect like your initial prototype design nozzle ends that spin the center) of the air in the system that might get trapped and start flowing directionally towards the exhaust, but now with air from the outside helping a little using some side air channels that have simple intakes and that all run towards the exhaust point. As it travels towards the exhaust, the spokes rotate, and more air continues flowing it grows more efficient. Especially if it was a plane flying, or car! Wooohoo! The video is on my Xenon
reality
channel.
You don't need a ball bearing when using PTFE. A smooth rod is good enough. And if you machine a small groove juts a little ways from the hole, and put a small O ring, greased with silicone grease, in it, you can get close to a perfect seal. Also, now where you have non-leaky "flap" design, I think it's worth experimenting with more flaps. Many more flaps. The available volume is constantly expanding (in the direction of rotation) so the pressure will always be the greatest on the flap facing the previous "compartment". Having more flaps will get you smaller amounts of air lost when they pass the exhaust outlet, so going as high as the geometry allows would be my first test.
As most have stated the housing can be made of teflon as well. Using a near interference fit for the shaft holes and let it run with the abrassive compound to wear in the shaft and housing to create the same near perfect seal. The rotor inside can be made to touch the case and wear in as well with the same method. This would make all of the parts fit to each other as closely as possible to seal off any leaks. Once the engine design and rotor assembly are perfected then worry about sealing the front doing away with the bearing or running a piece of teflon behind the bearing to seal bearing. Or spend the money for sealed bearings......
I think for the rotor-piston, you should put a teflon, or similar, washer seal/gasket between it and the front/back of the housing. This would drastically reduce the amount of air seeping "around" the piston on those two faces.
I would also recommend increasing the "hinge" of the flaps just ever so slightly so there's less fatigue on the hinge.