This is called a "motorjet" and I built one as a teenager about 30 years ago, I used it to successfully fly an RC airplane. Good for you for doing it, but in order for it to work the compressor must be able to develop an appreciable pressure ratio. Your compressor is of the style used in car turbochargers and must run MUCH faster than a 3D printed one can withstand. I made my compressor wheel out of model aircraft plywood and machined grooves in the outside diameter, then wrapped it with carbon fiber to keep it from blowing up at high RPM. I used a brushless DC motor to drive it directly at roughly 50,000 RPM and it produced around 3 PSI pressure IIRC, which was just barely enough for the engine to produce roughly 1 pound of thrust and fly the ~3 lb. RC plane. Fuel consumption was incredibly high, about 1 liter of fuel (diesel fuel/kerosene and gasoline mixed) for one minute of flight. It did work, though. So yes, this CAN work! But, your compressor must be able to develop a few PSI of pressure otherwise you won't have a jet engine--just a blowtorch. About 5 PSI pressure is a good number to work with, restrict the outlet of the compressor by covering it with your hand and see if you can get it to produce a few PSI without blocking all the airflow.
I got done tightening to tolerances today and the compressor made a static peak of 0.9psi at 30k rpm. When I designed it I had planned for it to spin at a maximum of 60k rpm, but the brushed motors we're extremely disappointing. Rather than upgrading the motor and compressor I've started working on a new turbojet engine, so I can just work on optimizing the engine and compressor directly without having to invest in brushless motors and ESCs. I really appreciate the input, thank you! Cheers✌️
@@Neally Brushless motors and ESCs are available from China quite cheap though. If you use a small car turbo compressor and a brushless motor you might be able to get useful thrust out of it, enough to fly an RC plane. A pressure of 0.9 PSI should be enough to get it to work, but with the motors going at full power the engine is basically idling. About 5 PSI or more would be good. The higher the compressor pressure, the more thrust you will get for a given fuel consumption and overall engine size. That's why passenger jet engines can run at compressor pressures of several hundred PSI :)
For sure, I'll keep the brushless motors in mind. But I was going to build the new engine soon anyways so I think I'll get cracking on that and then revisit this motorjet down the road once I have some more money.. Being a student is rough😂
@@Neally No doubt, but if you study engineering/technology then having projects like this will show you that designing something is one thing--but getting it actually BUILT so that it can WORK is a whole different ball game!
Perhaps one option he could pursue is to add a few axial compressor stages prior to the centrifugal (current compressor he is using). Don't know if this would add appreciable additional pressurization at lower rpms or not however. This is the problem with gas turbines. They require insanely fast rotational speeds to get any appreciable compression
This is great! You probably already know this but if not, you should consider getting a very high KV brushless motor and driving the comrpessor directly instead of using pulleys and those DC motors. They are much more powerful and efficient, especially at really high RPMS, which are needed for this compressor.
Yeah that's a really good idea! I was a little bit restricted by budget factors which kept me from exploring in that direction, but you're definitely right! I may look into it in the future. Thanks!
@@Neally That's an excellent idea because the timing belt and pulleys will absorb most of your motors' power output. Alternatively, you can use a plastic gear on the motor shaft and a small steel gear on the compressor shaft and run them without oil. That might work. This style of compressor (no cover plate, like a car turbo) must run at much higher speeds to produce enough air pressure, probably 3 to 5 PSI might do it. Youll probably have to get the compressor running at 50,000+ RPM to do that, and if it blows up, you'll need a different compressor design. Be careful around stuff that spins really fast--it can blow up like a small bomb! Not to shout but WEAR YOUR SAFETY GLASSES WHEN RUNNING IT.
Really, I 'never'wear safety glasses cause they allow material to bounce off the inside of the lense and into your eye cause the eye can't detect it quick enough, cause you obstructed it with the fukin plastic lense 😅 don't believe me! Then wake the fuk up! God gave us reflexes for a fukin reason 😮
bro the ceiling fan in my house makes more boost and cfm than this compressor, your gonna need a bigger exducer ngl to make it flow the way you want at that rpm.
@@johnmoseslives No he doesn't, he needs the compressor to withstand much higher RPM to get the pressure he needs for a jet engine to work. 3D printed plastic ain't gonna cut it, it will burst at high RPM. There's a reason they make compressors for turbos out of aluminum :) You also need a LOT of motor power for this to work, if those brushed motors are maybe 100 Watts each then the engine will barely idle. It'll be more like a blowtorch instead of a jet engine because there isn't enough air pressure. Instead of a couple hundred watts of power, maybe a kilowatt would be good.
As a young man back in the late 80s my buddy and I were always playing with a go-cart or mini bike or whatever. We decided we needed a supercharged go-cart. My buddy made one to fit a 5hp Briggs. Didn't work well. So I took it and made some big changes and it worked. The impeller was a washing machine water pump. Turned it into a manageable shape for the 9in south bend lath were were using. Had a 9-1 over drive with a v belt. Had studs in the engine. Shaves head. Massive ports. I ran it on 25% nitro rc helicopter fuel. It was a screaming beast. Absolutely dangerous as could be. Now with 3d printing. Hard to believe what is possible. We joked about making something from nothing. Never dreamed of stuff like this back then.
That's not a turbocharger... It is not powered using the engine's exhaust gasses. A turbo uses exhaust gasses. It's why a turbojet is called a turbojet
Maybe you could add another compression stage? The pressure seems quite low, as even the first jet engines had around a ratio of 2. Either axial (to act as a axial inducer and stabilize the flow before entering the centrifugal stage) or centrifugal, and perhaps a thrust augmentation nozzle like those tested by NACA? Though it is probably the jet engine itself that is the weak link, but given that you are working on a follow-up it probably doesn't matter. You should perhaps look at the Jumo 004B's combustion chamber for some inspiration, those reached 95% efficiency and compared to more modern ones, are easier to find and get your hands on.
The compressor speed is currently the limiting factor, I think if I add more stages it'll just slow down the motors more and negate any benefit. Like you said, I'm working on a new turbocharged project, and I'm designing it so that the compressor section is easily swapped out. I plan on testing centrifugal and axial compressors to see how they affect performance. Thanks, I appreciate it!
The fan show down series is looking for the fans with the highest static pressure this time, maybe you can get some inspirations from those designs.@@Neally
@@NeallyI mentioned this in another comment, but perhaps a free axial stages prior to your current centrifugal stage. I think there are designs that have two stage centrifugal, but that's the limit due to the forces experienced by the second compressor if I remember correctly
Thumbs up for you having a lathe! All of the hip 3D printing people I know dont have one. They think its some obsolete grandpa tool. They then proceed to show up every week to use my lathe :D
@@Neally If you're really crafty you can build damn near *anything* with only a lathe. No 3D printing, no milling machine, no CNC anything either. You need to buy or build an attachment for the vertical axis though because a lathe only has two horizontal ones (carriage and cross slide) so you need to 'fudge' the third axis.
Actual turbos spin around 130,000-150,000+ rpm so yeah…. Gonna need a lot more electric motor to run that thing… I am impressed you got a PLA compressor wheel to 30,000rpm though.
@@NeallyI mean I’d just rob a turbine from a junkyard turbo… gasoline engine turbo turbines are typically made from inconel steel as well which will take the heat.
My HVLP spray system has a 3 stage radial blower. They're just high pressure vacuum cleaner motors. Suspect the only way to get much higher outlet pressure with a 3d printed system is to add a stage. It will start to get warm however, so choice of print material would be important. On the combustion side. Are you making use of the propane to bootstrap air flow? By that i mean, heat it in the exhaust to vaporise it and generate a bit of pressure, then use the pressure in a venturi or air amplifier style nozzle to suck air into the combustion chamber. Looks fun. Wish there was enough time for such projects!
@@Neally Yeah, sometimes reality just sucks... I drive towards efficiency, even though I love turbines. They are getting better. Most people don't understand ICE. It's not the combustion that makes the power, but the expanding atmosphere it heats up. And in that atmosphere is water. Water to steam is 1000:1.
Very fun project I have some ideas that could help you out. It appears your centrifugal is having some compressor surge. Also you might find that adding a variable vane inlet. And also a bleed band on the compressor to help get past the hump of that surge zone. It looks like it’s having a hung start and you may find that having a duplex nozzle will help with that. Like having a fairly raw start fuel circuit and then slowly transition to primary fuel. Usually I start my turbines up around 12% n1 or compressor speed. Iirc around 34% is when we will make the swap from secondary to primary. There are some other things that can help too like maybe a diffuser.
Wow this is really detailed, thank you! I'll spend some time researching the stuff you're talking about, and I'll see how best to implement it. There is a diffuser but it's incorporated into the top of the volute, I think I may design it differently in the future. I appreciate the advice!
@@Neally hey no problem it’s such a cool project. I have often wanted to make something similar but as a independent power adder for cars etc. I overhaul turbines for a living so if you have any questions or your stuck on something lmk. Although I don’t actually know how to really use this you tube well.
Hey I know it’s a a lot harder for your size application but I’ve gotten small turbos about 1/4 the compressor wheel size of yours with resin printers, very similar numbers with FDM if not better for your use case. Got them up to 1psi at 60-70k rpm. Lot of heat develops at the blades after those numbers in resin prints in my tests. I say mess with scaling percentages in the decimal points and work on getting a tighter tolerance too on the housing
For sure! I'm working on a turbojet right now which should let me push the compressor a lot harder, so I'll do more testing on it then! 60-70k rpm is massive though, good on you for pulling it off
Remember, cars have at minimum a compression ratio of like 3-4, and they're already like only 30% efficient. Look up heat engine cycles and you'll see that getting a hugher compression ratio is the single most important thing for you to figure out at this point. One of the issues I think I see here is that your combustion chamber is larger in cross section than the inlet of your turbine, which means that you're actually expanding the gas when it should be squeezed as much as possible. Make a smooth throat, and do combustion in the throat. Make the throat as narrow as you need until you get an acceptable compression ratio. The reason regular turbines are the normal choice is because you get positive feedback, it's even possible to have runaway occur because of this. Whereas the electric motors will falter and peter out as speed increases. You'll also want to have a shell around the combustion chamber, and have flutes in the chamber so that cool air can keep the metal from melting when it's running as hot as it should be
Yeah, I was rather disappointed with the electric motors, but they were more of a proof of concept than anything else. I'm currently building a proper turbine engine to drive the compressor, so I'm sure well see some improvement very soon!
Man this is awesome, any chance of you uploading the STLs or step or....really anything thatll let me print one too to the thingyverse ya got listed? :) Anyhow, subbed :)
nice video dude, your different to other engineering creators but in a good way, your stuff looks professional clean and well done. i will recommend your channel to my friends that like this stuff
Nice project! I noticed that there was a bit of surging so maybe try messing with the length of the outlet pipe? This should improve your air fuel ratio even further and also provide a means of back pressure for your fan to fight against and thus build more pressure and more thrust
Yeah I'll play around with that and we'll see what happens. I ended up printing a new volute with tighter tolerances to make the gaps as tight as possible, and that increased the static pressure to nearly a full psi, I'm curious to see how that test run will go.. It should help at least a little bit with the surge issue
very nice! for the 3d prints that need to be printed together, are there any parameters that you need to set on the slicer? Ive been having trouble getting mine too fit
Buy the cheap modified iron with thread on tips for the threaded heat-set inserts. Even with that it’s hard to get them perfect enough to make a long screw even appear straight but it’s still extremely satisfying to watch them go in
@@Neally I would definitely build a press if I needed them to be perfect. I’ve been wanting to build a compressor like this for a long time so this is quite inspiring. There is another really good video on UA-cam about ducted fan theory you might find useful. Pretty sure it’s the only one of its kind
Yeah that's why I haven't yet, but definitely give it a shot, it's a super rewarding project! And send a link if you remember what it's called, cheers!
nice, but i think if you printed fan or an axial compresor with multiplying bldc motor from used hdd its will be a good project, you can adding motor in series flow and make it reverse spin every section
Neally, here's a similar idea but he uses an aluminum compressor from a turbocharger and it can withstand much higher RPM than a plastic one can, especially a 3D printed one. He's getting over 3 PSI pressure and his engine produces about 900 grams of thrust (about 2 pounds.) Here you go! ua-cam.com/video/b3q22EBB6Zk/v-deo.html
I think with a faster motor, and a more optimized design we might be able to get close to something like that too. It's really cool to see how similar the designs are too! Thanks!
I've been at it for a long time haha, I looked at some of your stuff and you're doing great. See if you can get yourself a 3d printer at some point and with a little bit of CAD you'll be able to make those engines come to life
how in the world does this have only 10k views? this is crazy good work, your content is really beautiful just subbed!!! edited my spellings and grammar, lost Neally's heart cuz of edit :(
It's a 30psi pressure transducer hooked up to an arduino. The transducer outputs 0.5v to 4.5v depending on the pressure making it pretty easy to use with the arduino
This guy is building a drinking jet engine while iterate on various thing, i actually speedrunned this and going to sub instantly, just one thing you need to proceed slowly enough to not stress out TOO MUCH, we want and must see your progress but keep in mind that you need to think to do this at the right pace for yourself!!!!
@@Neally Do both. Pulsed combustion increases thermodynamic efficiency, but reduces efficiency of a turbine section. Since you're not doing a turbine section, you won't have those loses. Of course, pulsed combustion noise isn't exactly neighborhood friendly. You're doing stuff I've dreamed of doing for a while. Integza channel is a huge motivator too, but I was interested in this stuff prior to that. Integza just shows you how much you can push 3d printing! I did a smaller logan style pulsejet a when I was a kid. Now I have a random turbo laying around, and I've tested 3d printing the compressor from Integza using Nylon Carbon Fiber. Also bought a propellor rpm meter. And I have glow plugs from my old diesel that I had hoped to use for liquid startup of a jet engine. :D But I have too many hobbies, so just haven't put it all together. Maybe as my kids get older,....
I would build a ducted fan rather than a compressor. A fan is much better at simply moving air to create thrust, since it doesn't waste energy on compressing the air. I need the compressor because it pressurizes the air for combustion, but the compressor itself doesn't really add much thrust
@@Neally Thanks for answering! So for propulsion like those in development human caring drones you can see everywhere on youtube it makes sense to have only ducted fans (or the axial compressor part of a axial jet engine) because of the reason you explained above, right? I am asking because I am thinking about what it's missing from those projects and I think they run for range and lose all best features they could get by using jet propulsion instead of propellers. And one thing I am thinking about is increased safety, simplicity and compactness with centrifugal compressors. So I am wondering if the loss is that significant.... considering range is not a first issue for my idea.
I don't have an exact number for you, but while testing the speed controller popped its 20amp fuse twice, and the motors run on 24v, so as a ballpark estimate I'd say something around 480 watts. The latest test I ran produces 484g of thrust... I feel like that ratio is pretty abysmal, but we'll improve it
Hi, im wanting to get my own 3d printer to make such impellers and usable components as well as foaming filament for plane components. What printer did you use here? Was it a resin or an fdm printer an what model was it?
You do want to actually choke the jet engine throat, tho. Won't get good thrust unless you do. But you need like a 1.9:1 pressure ratio for air at room temperature to get choked flow, so 0.7psi ain't gonna cut it. 12psi (above ambient) is probably required. So 17 of those boys combined. (temperature will get to about 165°F from compression if you do that, so need material that can handle that.)
Yeah I agree, I came to the same conclusion through my tests. Thrust went up until the compressor started surging because it wasn't producing enough pressure. I might design a new compressor to try to squeeze out a little more performance, but I've started working on a turbojet to avoid the motor problem as a whole
I used slow motion video to see where the imbalance caused the rotation to slow down while it was spinning in its bearings, and then used a hand file to remove enough material off the underside of the impeller wheel to balance it. It took a little bit but it worked decently well
Hello, why can't the compressor have a unique shaft with the turbine wheel so that you can, after the turbine gets to good RPM, turn off the electric motor and let it run using only the fuel and not the electric motor?
You can do that, it would be a turbojet at that point. I built this one to test different ideas and to see how it all works together. I'm currently working on building a new engine to do exactly that!
No it won't. It will allow you to use cheaper fuel, and very slightly less fuel for the same thrust. Using gasoline might make it easier to have ignition and combustion. When I built one of these back in the mid-'90s I used a mixture of diesel fuel and gasoline. A jet engine's power output (thrust) is primarily determined by its airflow capacity and its compressor pressure, not what kind of fuel you use.
Don't know where you live bro but I am pretty sure I heard you swear profusely when you dropped that off the bench and I live in Australia, cool video cheers.
I did test in a previous video. And pouring liquid propane into the engine wouldn't double and triple the thrust if was just the compressor producing thrust...
@@Neally What are you gunna strap the finished product to? if you dont mind my asking. May I suggest a classic original "Little Red Wagon" no mods just a 10 ft stream of shock diomands coming off the back. I gaurantee your channel will explode, and hopefully only just your channel, not the wagon.
I started working on a new engine yesterday that I plan putting in a small self built rc airplane, the idea of flying is fascinating to me and I wanna see if we can make it happen
What software or cad do you use to make stuff like this? I’m just getting into 3d printing but I want a good software to make cool stuff on eventually.
Personally I started on fusion 360, their non commercial version is free and I've been using it since I started. I had a chance to work with solidworks for a while and ended up returning to fusion because solidworks felt kinda clunky. Start with fusion, it's very user friendly and you'll get a feel for the basics, which carry over to other platforms.. Plus it's free🤷
I'm new to this, but an engine that cannot self sustain and that gets it's primary power from electricity is called a motor. In your case, I would venture you say that you have built an electric jet motor.
Interesting, I think you'd be right if the thrust were coming from the compressor, but the majority of thrust is a result of burning fuel so I believe it is a jet engine, by definition.
@@Neallyhow is it the majority if you had 450g on propane and 233g electric only? Depending on the motor used, static thrust in excess of 700 grams can be achieved at 200 W input with a simple electric ducted fan .... No need for propane nor a turbine nor your separate compressor at all. A ducted fan is so small, light, simple, reliable, wildly available, and cheap, and can outperform what you have here. The amount of energy you lose in the belt is way more than you think, ducted fan is direct drive.....
I live in the frozen wasteland of Canada, the use of imperial and metric simultaneously is extremely common here. I personally design using metric because I prefer it, but I'm often forced to use imperial parts because they're what available / affordable
@@Neally impressive I do prefer pla over petg for most of my projects but never thought that it could withstand such applications. Cool project and good content 😊
You're thinking of a turbojet, my build is technically a jet despite it not getting it's power from it's exhaust. I am work on a turbojet, it'll be done in a few weeks I think, and it'll be exactly what you're thinking of
I'm loving seeing your progress
Thank you! I appreciate it!
You should take notes integza. Both of you blow flames in a pipe and call it a jet. But he does it better...
Nice seeing you here
@integza you sir are the reason I got into rockets, thank you for your content!
the allfather hath spoken!
This is called a "motorjet" and I built one as a teenager about 30 years ago, I used it to successfully fly an RC airplane.
Good for you for doing it, but in order for it to work the compressor must be able to develop an appreciable pressure ratio. Your compressor is of the style used in car turbochargers and must run MUCH faster than a 3D printed one can withstand.
I made my compressor wheel out of model aircraft plywood and machined grooves in the outside diameter, then wrapped it with carbon fiber to keep it from blowing up at high RPM. I used a brushless DC motor to drive it directly at roughly 50,000 RPM and it produced around 3 PSI pressure IIRC, which was just barely enough for the engine to produce roughly 1 pound of thrust and fly the ~3 lb. RC plane.
Fuel consumption was incredibly high, about 1 liter of fuel (diesel fuel/kerosene and gasoline mixed) for one minute of flight. It did work, though.
So yes, this CAN work! But, your compressor must be able to develop a few PSI of pressure otherwise you won't have a jet engine--just a blowtorch. About 5 PSI pressure is a good number to work with, restrict the outlet of the compressor by covering it with your hand and see if you can get it to produce a few PSI without blocking all the airflow.
I got done tightening to tolerances today and the compressor made a static peak of 0.9psi at 30k rpm. When I designed it I had planned for it to spin at a maximum of 60k rpm, but the brushed motors we're extremely disappointing. Rather than upgrading the motor and compressor I've started working on a new turbojet engine, so I can just work on optimizing the engine and compressor directly without having to invest in brushless motors and ESCs. I really appreciate the input, thank you! Cheers✌️
@@Neally Brushless motors and ESCs are available from China quite cheap though. If you use a small car turbo compressor and a brushless motor you might be able to get useful thrust out of it, enough to fly an RC plane.
A pressure of 0.9 PSI should be enough to get it to work, but with the motors going at full power the engine is basically idling. About 5 PSI or more would be good. The higher the compressor pressure, the more thrust you will get for a given fuel consumption and overall engine size. That's why passenger jet engines can run at compressor pressures of several hundred PSI :)
For sure, I'll keep the brushless motors in mind. But I was going to build the new engine soon anyways so I think I'll get cracking on that and then revisit this motorjet down the road once I have some more money.. Being a student is rough😂
@@Neally No doubt, but if you study engineering/technology then having projects like this will show you that designing something is one thing--but getting it actually BUILT so that it can WORK is a whole different ball game!
Perhaps one option he could pursue is to add a few axial compressor stages prior to the centrifugal (current compressor he is using). Don't know if this would add appreciable additional pressurization at lower rpms or not however. This is the problem with gas turbines. They require insanely fast rotational speeds to get any appreciable compression
Nothing like the feeling of finding a cool new youtube channel
Good to have you along for the adventure, thank you!
This is great! You probably already know this but if not, you should consider getting a very high KV brushless motor and driving the comrpessor directly instead of using pulleys and those DC motors. They are much more powerful and efficient, especially at really high RPMS, which are needed for this compressor.
Yeah that's a really good idea! I was a little bit restricted by budget factors which kept me from exploring in that direction, but you're definitely right! I may look into it in the future. Thanks!
@@Neally That's an excellent idea because the timing belt and pulleys will absorb most of your motors' power output. Alternatively, you can use a plastic gear on the motor shaft and a small steel gear on the compressor shaft and run them without oil. That might work.
This style of compressor (no cover plate, like a car turbo) must run at much higher speeds to produce enough air pressure, probably 3 to 5 PSI might do it. Youll probably have to get the compressor running at 50,000+ RPM to do that, and if it blows up, you'll need a different compressor design.
Be careful around stuff that spins really fast--it can blow up like a small bomb! Not to shout but WEAR YOUR SAFETY GLASSES WHEN RUNNING IT.
Really, I 'never'wear safety glasses cause they allow material to bounce off the inside of the lense and into your eye cause the eye can't detect it quick enough, cause you obstructed it with the fukin plastic lense 😅 don't believe me! Then wake the fuk up! God gave us reflexes for a fukin reason 😮
bro the ceiling fan in my house makes more boost and cfm than this compressor, your gonna need a bigger exducer ngl to make it flow the way you want at that rpm.
@@johnmoseslives No he doesn't, he needs the compressor to withstand much higher RPM to get the pressure he needs for a jet engine to work. 3D printed plastic ain't gonna cut it, it will burst at high RPM. There's a reason they make compressors for turbos out of aluminum :)
You also need a LOT of motor power for this to work, if those brushed motors are maybe 100 Watts each then the engine will barely idle. It'll be more like a blowtorch instead of a jet engine because there isn't enough air pressure. Instead of a couple hundred watts of power, maybe a kilowatt would be good.
As a young man back in the late 80s my buddy and I were always playing with a go-cart or mini bike or whatever. We decided we needed a supercharged go-cart. My buddy made one to fit a 5hp Briggs. Didn't work well. So I took it and made some big changes and it worked. The impeller was a washing machine water pump. Turned it into a manageable shape for the 9in south bend lath were were using. Had a 9-1 over drive with a v belt. Had studs in the engine. Shaves head. Massive ports. I ran it on 25% nitro rc helicopter fuel. It was a screaming beast. Absolutely dangerous as could be. Now with 3d printing. Hard to believe what is possible. We joked about making something from nothing. Never dreamed of stuff like this back then.
3d printers are pretty good, but I think what you did with that waterpump takes a lot more creativity and skill. That sounds like an epic project!
@Neally Thank you. It was a couple of years worth of fun. My mom would say. At least he doesn't drink... lol
Turbocharged jet engine! Integza would be proud!
Thank you!
That's not a turbocharger... It is not powered using the engine's exhaust gasses. A turbo uses exhaust gasses. It's why a turbojet is called a turbojet
@@amicloud_yt 🤓🤓🤓
@@nervun8097 Imagine mocking technical discernment on a markedly technical video for technical people.
~Major Aerospace manufacturers hate this one WEIRD trick to add %30 more to your turbine engine!~
"click here to find hot local turbojets in your area" 😂
wow randomly found this video, nice bro
Thanks bro✌️
Maybe you could add another compression stage? The pressure seems quite low, as even the first jet engines had around a ratio of 2. Either axial (to act as a axial inducer and stabilize the flow before entering the centrifugal stage) or centrifugal, and perhaps a thrust augmentation nozzle like those tested by NACA? Though it is probably the jet engine itself that is the weak link, but given that you are working on a follow-up it probably doesn't matter. You should perhaps look at the Jumo 004B's combustion chamber for some inspiration, those reached 95% efficiency and compared to more modern ones, are easier to find and get your hands on.
The compressor speed is currently the limiting factor, I think if I add more stages it'll just slow down the motors more and negate any benefit. Like you said, I'm working on a new turbocharged project, and I'm designing it so that the compressor section is easily swapped out. I plan on testing centrifugal and axial compressors to see how they affect performance. Thanks, I appreciate it!
Great video!
I would be interested in the files for the turbo if they are available.
This quality of video vs subscriber count is grossly underrated. I thought i stumbled on a 500k+ channel lol
I really appreciate that, thank you!
This is so cool but im pretty sure with a propeller and those two dc motors you could generate even more thrust
That sounds like a very interesting experiment👀
I have no idea how I ended up on this video, but this is an awesome project! Super interesting!
Glad you enjoyed it!
Nice, maybe a two stage compressor to get even more airflow and higher pressure? Maybe two first stage inputs feeding into one secondary stage?
Yeah for sure! I was considering making and axial compressor, but a two stage would definitely work too!
The fan show down series is looking for the fans with the highest static pressure this time, maybe you can get some inspirations from those designs.@@Neally
@@NeallyI mentioned this in another comment, but perhaps a free axial stages prior to your current centrifugal stage. I think there are designs that have two stage centrifugal, but that's the limit due to the forces experienced by the second compressor if I remember correctly
i am dumb i thought that's 902K subs how the heck you are so underrated man so much work and efforts. 9.02k?
SUBBED
Cheers, friend! Thank you!
Hidden Gem of a channel!
Glad to hear it, thanks!
Thumbs up for you having a lathe! All of the hip 3D printing people I know dont have one. They think its some obsolete grandpa tool. They then proceed to show up every week to use my lathe :D
Oh they're invaluable! I have not regretted getting one, even just a little one is better than none😂
@@Neally If you're really crafty you can build damn near *anything* with only a lathe. No 3D printing, no milling machine, no CNC anything either. You need to buy or build an attachment for the vertical axis though because a lathe only has two horizontal ones (carriage and cross slide) so you need to 'fudge' the third axis.
UA-camr Paul's Garage is using 3d printed masters to sand cast parts for a DIY lathe.
Actual turbos spin around 130,000-150,000+ rpm so yeah…. Gonna need a lot more electric motor to run that thing… I am impressed you got a PLA compressor wheel to 30,000rpm though.
Or say screw the electric motor and build a turbine to drive it instead 👀
@@NeallyI mean I’d just rob a turbine from a junkyard turbo… gasoline engine turbo turbines are typically made from inconel steel as well which will take the heat.
Channel seems underrated; hope it takes off 🤙
You and me both, thank you!
My HVLP spray system has a 3 stage radial blower. They're just high pressure vacuum cleaner motors. Suspect the only way to get much higher outlet pressure with a 3d printed system is to add a stage. It will start to get warm however, so choice of print material would be important.
On the combustion side. Are you making use of the propane to bootstrap air flow? By that i mean, heat it in the exhaust to vaporise it and generate a bit of pressure, then use the pressure in a venturi or air amplifier style nozzle to suck air into the combustion chamber.
Looks fun. Wish there was enough time for such projects!
I was trained on the T56A-14 Turbo prop. 4600 SHP output. 20,000 HP input to compressor. Just a FYI perspective.
Yeah those are definitely some crazy numbers.
@@Neally Yeah, sometimes reality just sucks... I drive towards efficiency, even though I love turbines. They are getting better. Most people don't understand ICE. It's not the combustion that makes the power, but the expanding atmosphere it heats up. And in that atmosphere is water. Water to steam is 1000:1.
Very fun project I have some ideas that could help you out.
It appears your centrifugal is having some compressor surge.
Also you might find that adding a variable vane inlet. And also a bleed band on the compressor to help get past the hump of that surge zone.
It looks like it’s having a hung start and you may find that having a duplex nozzle will help with that. Like having a fairly raw start fuel circuit and then slowly transition to primary fuel. Usually I start my turbines up around 12% n1 or compressor speed.
Iirc around 34% is when we will make the swap from secondary to primary.
There are some other things that can help too like maybe a diffuser.
Wow this is really detailed, thank you! I'll spend some time researching the stuff you're talking about, and I'll see how best to implement it. There is a diffuser but it's incorporated into the top of the volute, I think I may design it differently in the future. I appreciate the advice!
@@Neally hey no problem it’s such a cool project. I have often wanted to make something similar but as a independent power adder for cars etc.
I overhaul turbines for a living so if you have any questions or your stuck on something lmk. Although I don’t actually know how to really use this you tube well.
Cool stuff!!!
Thanks!
Very cool stuff🙌🙌💯… can you tell me what sensor are you using for measuring pressure and thrust?
Pressure is measured by a 30psi pressure transducer, and thrust by a 20kg load cell! Thanks!
Hey I know it’s a a lot harder for your size application but I’ve gotten small turbos about 1/4 the compressor wheel size of yours with resin printers, very similar numbers with FDM if not better for your use case. Got them up to 1psi at 60-70k rpm. Lot of heat develops at the blades after those numbers in resin prints in my tests. I say mess with scaling percentages in the decimal points and work on getting a tighter tolerance too on the housing
For sure! I'm working on a turbojet right now which should let me push the compressor a lot harder, so I'll do more testing on it then! 60-70k rpm is massive though, good on you for pulling it off
Remember, cars have at minimum a compression ratio of like 3-4, and they're already like only 30% efficient. Look up heat engine cycles and you'll see that getting a hugher compression ratio is the single most important thing for you to figure out at this point. One of the issues I think I see here is that your combustion chamber is larger in cross section than the inlet of your turbine, which means that you're actually expanding the gas when it should be squeezed as much as possible. Make a smooth throat, and do combustion in the throat. Make the throat as narrow as you need until you get an acceptable compression ratio.
The reason regular turbines are the normal choice is because you get positive feedback, it's even possible to have runaway occur because of this. Whereas the electric motors will falter and peter out as speed increases. You'll also want to have a shell around the combustion chamber, and have flutes in the chamber so that cool air can keep the metal from melting when it's running as hot as it should be
Yeah, I was rather disappointed with the electric motors, but they were more of a proof of concept than anything else. I'm currently building a proper turbine engine to drive the compressor, so I'm sure well see some improvement very soon!
I demand the next video NOW great stuff
I'm working on it😂
Man this is awesome, any chance of you uploading the STLs or step or....really anything thatll let me print one too to the thingyverse ya got listed? :) Anyhow, subbed :)
Yep I'm working on posting stuff for you guys!
nice video dude, your different to other engineering creators but in a good way, your stuff looks professional clean and well done. i will recommend your channel to my friends that like this stuff
Thank you, friend! I appreciate it!
@@Neally i love your stuff so far and expect even more in the future as your channel grows, you should be good tho cus you only cook up great vids
This is awesome u think we can mount one in the back of ny Challenger and it would go faster? 😊
I don't know if it would do much for you as it is right now, but we definitely could😂
You may need to adjust the loudness settings on your video to match youtube's standard.
Nice project! I noticed that there was a bit of surging so maybe try messing with the length of the outlet pipe? This should improve your air fuel ratio even further and also provide a means of back pressure for your fan to fight against and thus build more pressure and more thrust
Yeah I'll play around with that and we'll see what happens. I ended up printing a new volute with tighter tolerances to make the gaps as tight as possible, and that increased the static pressure to nearly a full psi, I'm curious to see how that test run will go.. It should help at least a little bit with the surge issue
Happy to hear! Pressure is a funny thing @@Neally
very nice! for the 3d prints that need to be printed together, are there any parameters that you need to set on the slicer? Ive been having trouble getting mine too fit
I didn't do anything special on the slicer, but I designed the parts with certain tolerances in mind to have it all fit smoothly
@Neally would an example be like if it was 15mm you would scale it down 1 or 2 mm just in case it would expand I'm guessing?
Compound the two! Hope you don’t melt the second impeller though
That's a cool idea, I maybe try something similar with the new engine!
This is so GOOD!
Glad you guys think so!
Buy the cheap modified iron with thread on tips for the threaded heat-set inserts. Even with that it’s hard to get them perfect enough to make a long screw even appear straight but it’s still extremely satisfying to watch them go in
Agreed, I should build a linear press for them
@@Neally I would definitely build a press if I needed them to be perfect. I’ve been wanting to build a compressor like this for a long time so this is quite inspiring. There is another really good video on UA-cam about ducted fan theory you might find useful. Pretty sure it’s the only one of its kind
Yeah that's why I haven't yet, but definitely give it a shot, it's a super rewarding project! And send a link if you remember what it's called, cheers!
@@Neally it’s called “how to apply ducted fan theory to real world fans” by Wymans Workshop
Awesome, thank you!
Could you do a video on how the impeller is designed
I was thinking about designing a different impeller for the compressor, so I may get around to doing that!
It looks great!! Are you using PLA or ABS?
PLA for now!
nice, but i think if you printed fan or an axial compresor with multiplying bldc motor from used hdd its will be a good project, you can adding motor in series flow and make it reverse spin every section
I want to start working on an axial compressor very soon!
I am just amazed you can 3D print an impeller and it withstands 20K RPM :O
Lol yeah I was wondering how much it can actually take before blowing up.. I wanna see if I can push it to 40-50k😂
The bigger the turbo the more that jet going bang
Neally, here's a similar idea but he uses an aluminum compressor from a turbocharger and it can withstand much higher RPM than a plastic one can, especially a 3D printed one. He's getting over 3 PSI pressure and his engine produces about 900 grams of thrust (about 2 pounds.) Here you go!
ua-cam.com/video/b3q22EBB6Zk/v-deo.html
I think with a faster motor, and a more optimized design we might be able to get close to something like that too. It's really cool to see how similar the designs are too! Thanks!
Hey may be using a digital motor will produce more thrust
But i think that you should try a metallic centrifugal impeller😊
I may look into it! I've got a new brushless one that I'm gonna try out at some point
this puts my homemade back yard shenanigans to shame
I've been at it for a long time haha, I looked at some of your stuff and you're doing great. See if you can get yourself a 3d printer at some point and with a little bit of CAD you'll be able to make those engines come to life
@@Neally thats the plan just might be a couple years cause a pickup truck was not cheap
Damn that peek-RPM at 30.000.000 (MILLION ?!) 4:32
I think it's just some sort of interference on the hall effect sensor, it does the same thing at lower rpm too
how in the world does this have only 10k views? this is crazy good work, your content is really beautiful just subbed!!!
edited my spellings and grammar, lost Neally's heart cuz of edit :(
Thank you, friend! I appreciate it 🤟
I got you😂
@@Neally 😍🤩
lovely to see how you will blow up for sure keep up the good work
Thank you! Will do!
Exploding is very important for science.
have you published the 3d models for this anywhere? I could use a turbine like that for a project I'm working on
I'm working on making something available!
I am curious about the Static pressure tester "the boxduino" what components did you use? Id love to build one
It's a 30psi pressure transducer hooked up to an arduino. The transducer outputs 0.5v to 4.5v depending on the pressure making it pretty easy to use with the arduino
@@Neally thanks man I like what your doing keep up the good work
This guy is building a drinking jet engine while iterate on various thing, i actually speedrunned this and going to sub instantly, just one thing you need to proceed slowly enough to not stress out TOO MUCH, we want and must see your progress but keep in mind that you need to think to do this at the right pace for yourself!!!!
Thank you, I do have to keep that in mind because I get carried away sometimes. I appreciate it🤟
What are you using to measure the pressure at the outlet of the compressor?
A 30psi pressure transducer for oil/water, it works just the same with air
that's really cool dude, next project I really recommend you to work on a pulse jet engine, those a really cool and easier too.
Great idea! I'm working on a turbo jet right now, but maybe I'll build a pulse jet after that one👌
@@Neally Do both. Pulsed combustion increases thermodynamic efficiency, but reduces efficiency of a turbine section. Since you're not doing a turbine section, you won't have those loses. Of course, pulsed combustion noise isn't exactly neighborhood friendly.
You're doing stuff I've dreamed of doing for a while. Integza channel is a huge motivator too, but I was interested in this stuff prior to that. Integza just shows you how much you can push 3d printing! I did a smaller logan style pulsejet a when I was a kid. Now I have a random turbo laying around, and I've tested 3d printing the compressor from Integza using Nylon Carbon Fiber. Also bought a propellor rpm meter. And I have glow plugs from my old diesel that I had hoped to use for liquid startup of a jet engine. :D But I have too many hobbies, so just haven't put it all together. Maybe as my kids get older,....
I think my neighbours probably already hate me so there's not much to lose in that department.😂 That's a really cool idea though, I'll look into it!
how would you change the compressor so it creates (useful) thrust without the fuel burning chamber?
I would build a ducted fan rather than a compressor. A fan is much better at simply moving air to create thrust, since it doesn't waste energy on compressing the air. I need the compressor because it pressurizes the air for combustion, but the compressor itself doesn't really add much thrust
@@Neally Thanks for answering!
So for propulsion like those in development human caring drones you can see everywhere on youtube it makes sense to have only ducted fans (or the axial compressor part of a axial jet engine) because of the reason you explained above, right?
I am asking because I am thinking about what it's missing from those projects and I think they run for range and lose all best features they could get by using jet propulsion instead of propellers.
And one thing I am thinking about is increased safety, simplicity and compactness with centrifugal compressors. So I am wondering if the loss is that significant.... considering range is not a first issue for my idea.
damn when the video ended i was like, this dude is actually doing cool shit, he earned a sub. lmaoo.
Cool shit is the only stuff worth doing, thanks bro!
Liquid fuel yes!!!
How are you getting so many RPM out of 3d printed parts… that’s amazing.
I don't even know.. But it's holding up shockingly well, which makes me wanna push it even harder😂
You may have felt this video was cursed, but it definitely earned you a new sub here! 🤣
Haha I'm glad, thank you!
How much power does the compressor use? And how does it compare to thrust value?
I don't have an exact number for you, but while testing the speed controller popped its 20amp fuse twice, and the motors run on 24v, so as a ballpark estimate I'd say something around 480 watts. The latest test I ran produces 484g of thrust... I feel like that ratio is pretty abysmal, but we'll improve it
Hi, im wanting to get my own 3d printer to make such impellers and usable components as well as foaming filament for plane components. What printer did you use here? Was it a resin or an fdm printer an what model was it?
I used an ender 3 s1 pro for this build!
Do you think i could pull of the same thing with an ender 3 v3 ke or should i save up a bit extra for the s1 pro?@@Neally
Also what filament have you found works best for high speed rotating components?@@Neally
Pla and Petg are great
We need like 50 youtubers + Michael Reeves to make a gimbaling rocket engine with like 20 pounds of thrust.
With that many brains we could probably put a rocket in space😂
over 100 g is not much, but how great that someone create a homemade jet engine, pls make a bigger one, pls
In my most recent test it made 500g, but a bigger engine is on the way!
Should definitely put it in a Honda Civic
Agreed. That civic is gonna go Mach 8
You do want to actually choke the jet engine throat, tho. Won't get good thrust unless you do. But you need like a 1.9:1 pressure ratio for air at room temperature to get choked flow, so 0.7psi ain't gonna cut it. 12psi (above ambient) is probably required. So 17 of those boys combined. (temperature will get to about 165°F from compression if you do that, so need material that can handle that.)
Yeah I agree, I came to the same conclusion through my tests. Thrust went up until the compressor started surging because it wasn't producing enough pressure. I might design a new compressor to try to squeeze out a little more performance, but I've started working on a turbojet to avoid the motor problem as a whole
what is the material for the impeller?
Plain PLA!
@@Neally ngl i was not expecting that, thank you
well done!
Much appreciated!
i have a good idea to make more thrust it woud eat more fule but a afterburner
Love it! I'll be working on something like that very soon ;)
Wow!!! 👏
Thank you!
Keep it up, I love the content. I subscribed
Thank you! Will do 🤟
Is there some way I can download the stl files for the compressor? I want to build it myself so I can run my seventy five cc engine with it.
Is thera a way i can get these files to this compressor 😊
Yeah I'm putting the files together right now, I'll announce it in the video on Saturday!
Do you think this possible with car turbo ?
Oh for sure! It would be even better with one of those
what sensor for you use for rpm and pressure? i am curious
Hall effect sensor for rpm, and a pressure transducer for the pressure
One of these days makers will realize resin printers exist and produce accurate and smooth parts. One day...
I mean it's something I plan on getting eventually, but I prioritized other tools, like the lathe and tig welder
How did you balance your rotating assembly?
I used slow motion video to see where the imbalance caused the rotation to slow down while it was spinning in its bearings, and then used a hand file to remove enough material off the underside of the impeller wheel to balance it. It took a little bit but it worked decently well
Bro is the American integza
Hello, why can't the compressor have a unique shaft with the turbine wheel so that you can, after the turbine gets to good RPM, turn off the electric motor and let it run using only the fuel and not the electric motor?
You can do that, it would be a turbojet at that point. I built this one to test different ideas and to see how it all works together. I'm currently working on building a new engine to do exactly that!
@@Neally what is the technical name for this turbine you build? Not turbojet but what’s it called?
Running with Diesel will make your engine produce more power
That's the plan! Kerosene injection is the idea for the next video
No it won't. It will allow you to use cheaper fuel, and very slightly less fuel for the same thrust. Using gasoline might make it easier to have ignition and combustion.
When I built one of these back in the mid-'90s I used a mixture of diesel fuel and gasoline.
A jet engine's power output (thrust) is primarily determined by its airflow capacity and its compressor pressure, not what kind of fuel you use.
UA-cam randomly referred me to this video due to the 3D printing hashtag
Strange, it's almost as if it's about a fully 3d printed compressor😉 cheers!
why you don't use a brushless motor ?
I was using what I had on hand because I am a broke student and can't afford anything better😂
@@Neally understandable
Don't know where you live bro but I am pretty sure I heard you swear profusely when you dropped that off the bench and I live in Australia, cool video cheers.
You've got good ears, friend😂 Cheers from Canada!
Don't worry m8, it'll disassemble itself. 😂
Shockingly, it's held up pretty well so far 😂
Do you think you could 3D print a compressor that is similar in performance to the speed master P2 alexLTD uses for his electric supercharger ?
I can look into it!
@Neally dude that would be huge If it's possible to pull something like that off!
my question is, is the thrust due to the motor blowing air, or is it actually combustion. gotta test them separately to find out.
I did test in a previous video. And pouring liquid propane into the engine wouldn't double and triple the thrust if was just the compressor producing thrust...
could a 50cc with a fan not make more thrust? lol
Oh definitely, but where's the fun in that.. It's much better to struggle and suffer to produce mere grams of trust😂
Thats what its about, to suffer is character building 😂😂 well done
Definitely😂 thanks!
Danke für das gute Video.👍❤
❤️
I wanna see shock diamonds, more boost!
Me too! We'll get there eventually👌
@@Neally looking forward to it!
@@Neally What are you gunna strap the finished product to? if you dont mind my asking. May I suggest a classic original "Little Red Wagon" no mods just a 10 ft stream of shock diomands coming off the back. I gaurantee your channel will explode, and hopefully only just your channel, not the wagon.
I started working on a new engine yesterday that I plan putting in a small self built rc airplane, the idea of flying is fascinating to me and I wanna see if we can make it happen
@@Neally nice
What software or cad do you use to make stuff like this? I’m just getting into 3d printing but I want a good software to make cool stuff on eventually.
Personally I started on fusion 360, their non commercial version is free and I've been using it since I started. I had a chance to work with solidworks for a while and ended up returning to fusion because solidworks felt kinda clunky. Start with fusion, it's very user friendly and you'll get a feel for the basics, which carry over to other platforms.. Plus it's free🤷
@@NeallyThank you!
Of course!
Why do you have calipers on a spinning shaft?
WOW!
Thanks!
I'm new to this, but an engine that cannot self sustain and that gets it's primary power from electricity is called a motor. In your case, I would venture you say that you have built an electric jet motor.
Interesting, I think you'd be right if the thrust were coming from the compressor, but the majority of thrust is a result of burning fuel so I believe it is a jet engine, by definition.
@@Neallyhow is it the majority if you had 450g on propane and 233g electric only? Depending on the motor used, static thrust in excess of 700 grams can be achieved at 200 W input with a simple electric ducted fan .... No need for propane nor a turbine nor your separate compressor at all. A ducted fan is so small, light, simple, reliable, wildly available, and cheap, and can outperform what you have here. The amount of energy you lose in the belt is way more than you think, ducted fan is direct drive.....
Why do you use psi when all your other measurements are in metric?
I live in the frozen wasteland of Canada, the use of imperial and metric simultaneously is extremely common here. I personally design using metric because I prefer it, but I'm often forced to use imperial parts because they're what available / affordable
So like what about getting it to 50,000 rpm
That was my original goal for the compressor, but I severely disappointed by the performance of the DC motors
Run 4 motors and have the ratio for higher rpm
Haha yeah that might work, but it would look pretty wild
can you release the files i wanna use this as a fan and a turbo for a small engine.
The next logical step. I know your pain.
Heartbreaking 😂
What Filament do you use for this ?
Shockingly, standard PLA. The airflow currently keeps everything cool enough not to deform
@@Neally impressive I do prefer pla over petg for most of my projects but never thought that it could withstand such applications. Cool project and good content 😊
But this is not a jet engine.. the compressor is powered by an electric motor instead of turbine after the combustion chamber.
is this temporary?
You're thinking of a turbojet, my build is technically a jet despite it not getting it's power from it's exhaust. I am work on a turbojet, it'll be done in a few weeks I think, and it'll be exactly what you're thinking of
No gloves when using a lathe.
Yeah you're right, but it's really bloody cold in the shop so I'm doing my best to be careful while not catching frostbite
Ah yes the safety Safari right on time
Share the CAD files for those of us who want to print this?
Yeah I'll make something available in a little bit
what if you used a jet engine to spool a car turbo and put that turbo on a crown victoria because those things are indestructible
I'd say skip the jet and just turbocharge the Vic as is😂
for redneck science