Those type of impellers are used for pumping air, like in a turbo. Look at the exhaust side of a turbo for better ideas 🤘🏻👌🏻

@mitchellstrobbe7779

Жыл бұрын

Yes I can definitely agree his turbines resemble impellers.

@LuxGamer16

Жыл бұрын

Commenting so it stays on top. Correct assumption 👍

@Teth47

Жыл бұрын

I second this, the impeller and turbine have very different geometries. The impeller is meant to compress, it's optimized to convert kinetic energy into pressure, not the other way around. The turbine is meant to convert pressure into kinetic energy.

@forloop7713

Жыл бұрын

The compressor and turbine in a turbo look actually very similar

@Nitrolord1

Жыл бұрын

I agree with what these guys are saying but to simplify it you need to design the the fuel side impeller for pushing liquid instead of being designed the same as the airside impeller.

I'm still waiting for your next episode!

you gotta be making more content. this is a awesome project concept!

Overlaying the graph results on the footage of the run is absolutely beautiful. Wonderful editing and effort. I love being able to see the live data with the test in the background such a win man👍🏼

FreeCAD has plugins for fluid dynamics simulations and shaping turbine blades, might be helpful. Personally I haven't figured out how to do much with the turbine plugin but the fluids one isn't super difficult to get used to. With a little AutoCAD experience, FreeCAD itself can seem like something Shaggy and Scooby dreamed up in the Mystery Machine after hitting the scooby snacks too hard, but it does have its advantages once you bend your mind the right way.

Hi! Great video. Some notes: 1) you could also try adjusting input/output area of the turbine, it also plays a great role 2) in a "real" rocket, pressure will gradually go lower over time. a better testing strategy to measure efficiency here could be to gradually (and automatically) lower pressure, and instead of peak thrust measure the area under the thrust curve (total impulse) 3) pumping air is too different from pumping a liquid (requires less torque and more RPM to be efficient). IMO these results won't convert well

Stators might be a good idea. Also, if you look at turbines on car engines, the blades are curved on the outer rim, bent towards the airflow. I think the thing you're going for with a turbine is to get the air "impact angle" at something like a 45 degree angle, even as the blade moves away from the airflow.

I would also recommend to make multiple iterations on clearance between the housing and the impeller to find the most efficient one, nice what you did in this video 👍

I have been waiting for this video for ages!!! So glad you're back!!!

Your projects are excellent. Thank you for sharing them and please share more!

If you put graphene on the bearings, at the very least, you may get significant friction reduction. You may want to mix with oil, for better retention during testing. GREAT JOB!

According to google I am a chemical technician. That's why I work a lot with pumping gas/liquids and of course also with large NH3 heat pumps. This is an awesome project. Knowledge is good but testing is more fun ;-)

Loved the live force-time plot

Bro, to protect the combustion chamber you can cover the interior of the combustion chamber with a ablative material called starlite. You search how to make it on KZread.

Some thoughts for optimization: 1. It would be ideal to include a thrust bearing in this setup in addition to the radial bearing you included, as I would bet the thrust loading is being borne by either the balls in the bearing or the plastic of the housing rubbing, which would hurt efficiency. 2. It is very likely the case that the optimal rotational velocity for the turbine is much faster than the optimal rotational velocity for the propeller. Consider using a belt drive for reduction to get more thrust for the same inlet pressure. Love the video!

Another fun video -- happy to see you back! Hoping to see more from you soon!

pls continue making more content

So good to see another video from you!

Hi maybe you should look at the clearance between the propeller and the body. it could be an area for improvement. thank for the video

been waiting for more! Great to see another !

You could add a diffuser so that the air has a better more efficient path of flow and you can try an enclosed impeller which are more efficient than an open impeller

Equations for turbines can be found on several difrent NASA SP s (Special Publication) you can find these on the NASA STI server. Conveniently I have chosen a 3D printed air driven turbo pump for my scince fair project this year drawing some inspiration from your video 7 months ago. Axial and staged impulse/ reaction turbines are much better suited for pumping fluid because they can provide more torque at higher RPM with the same flow/presure.

Nice work, well executed.

Excellent work sir. It’s the resin prints for me

Turbines are awesome!

I’d love it if you could find a way to test the same impellers with a VGT set up.

Great video!

Welcome back we miss you

Always look forward to your videos

I like the verse at the end.

Please come back

Did you balance the propeller on the shaft? In the first shot of it spinning it doesn't look very balanced, witch could lead to increase friction in the bearings und thus lower efficiency. P.S.: Love your videos, good to see you back!

@Sciencish

Жыл бұрын

No I didn’t, I started to but then realized the turbines were just all warped during the printing/curing process. Thanks, it’s nice to finally post again!

one other thing to take into account is variability in speed , the efficiency of the turbines could change at different speeds so it'd be interesting to see if the results change when you use a smaller prop.

The king returns!

Really cool video! I need a 3d printer now!

Check out the exhaust/hot side of a turbocharger. Housing and turbine. They are pretty tightly fit for clearance between the turbine wheel and housing so no exhaust is waisted If you can reproduce this in a smaller scale this will produce phenomenal results and hopefully you have a propeller strong enough for the high rpm output. Will be like a jet turboprop just powered by high pressure air instead of jet A fuel.

Very interesting video

HE IS BACK!!

Compressed oxygen tanks (including the tiny torch sized ones) are 800 psi. Depending on the pump pressure curve, wouldn't that possibly achieve high enough pressure to overcome the chamber pressure?

The test load (large propeller) may not reflect the performance of the turbines in driving the actual intended load...Impedance matching may be a thing?

Nice

Nice project. Would you mind to redo a measure inverting inlet and exhaust on your turbines ? I have a strange feeling.

How about a 2 stage turbine? And maybe try a pelton turbine concept. Also, you should measure power, not trust, cuz some turbines might perform better at different speeds, or have higher torque, others higher top speed

Hi! I made some impellers out of wire cube storage brackets. They are plastic and have 8 straight blades arranged in parallel pairs. The gap between the centers of each set of the parallel blades is about 23% of the total diameter of the impeller. The blade pairs meet at the shaft and the shaft blocks the gaps between the pairs. I don't plan to replace them unless their performance is totally dismal -- and I don't expect it will come to that. But if you could test a similar design and compare it to the others, that would be awesome! Thank you in advance if you do!

He's back!

He’s not dead yay

search term you should loo for : " radial turbine velocity triangle" equations are time consuming to solve and not simple , that the rason for they use CFD. but the principle is that the air comes at a vectorial angle that depend on lift of the blade speed of the air and pressure. You should considere that each blade is actualy a wing that curve arround the axle torque and speed will also depend on the radius of course, and it will vari from the whole radius. the principal is th same as a propeler whre you trust depend on angl of atack naca profile and radius and pitch at each distance of the center. so you have to figure out te formula for a particular point on th radius an itegrate all the point (integral equation)

Optimized mix with curved blade? I love your channel.

What I think is happening with the offsets is that the air exiting the center is interfering with air coming from the channel opposite.

Great work 💪, if only I had a 3d printer xd

also look a ton of video from borg turbo and garett turbo wich explains the principle of a turbine.

those turbines shaft look wobbly, maybe a bearing + shaft on the other side too?

Hello! Your test at 0:56 probably did not fail because it was inherently bad. It failed because too much propellant pooled into your combustion chamber before ignition. In rocketry, this is known as a “hard start”. This can be solved by having the ignitor close to your injector at time of ignition, or starting with a small flowrate to achieve some combustion in your bottle and then crank it up to full flow. Great video!

Turbines need high rpm to work efficiently, you should use a very small propeller, so it reaches higher rpm.

Try a Tesla turbine, but be sure to make circles have low surface friction to make that thing works.

You can improve a lot the efficiency of the turbine by making it spin faster, this is because the smaller a turbine is the faster it needs to spin to have high efficiencies. (you can guess the optimal speed by looking at the Balje diagram for turbines and adimensional theory of fluid machines)

I'm no expert here, but I'll bet they'll produce different amounts of flow when pumping that may not necessarily correlate to the results when you're spinning them under pressure. It'd be cool to compare those results to these. Also -- subscribed!

Not a fan of music that's highly repetitive. Had my headphones on the table for most of the video. But a cool project anyway! Thanks for the upload!

Does a turbine work the same with water as with air? I don't know the answer, but I feel like the viscosity of water would cause it to act differently than air, thus the most optimum turbine for both might not be the same.

You should make it fully 3d printed on FDM and with fidget spinner bearings I made one like that but I also 3d printend bearing didn’t work it turned but not great (btw this test is a torque setup not rpm or pumping power unscientific but fun)

if you try water im sure other two would be proven but air it doesnt work i like purple one because it have bigger impact bigger improvements i cant tell if it big disadvantaged reverse flows it worth try

Nice! Which software did you use for turbines?

@Sciencish

Жыл бұрын

Fusion 360!

smol rotors cute

Why dont you see turbines used on air tools as reference? Seems like a good idea to reference something that already uses air for work.

Grey for pumping liquid and blue for the air side

its the centrifugal force, nothing else

@Jkauppa

Жыл бұрын

try removing the conical shape, just "flat" turbine with curves or straight

@Jkauppa

Жыл бұрын

should not matter

@Jkauppa

Жыл бұрын

that shape can be a horizontal wind turbine design as well

I think you should support the turbines with two bearing and maybe a metal shaft. Two bearing so it doesn't wobble. bye!!

Use carbon foam for your insulation in the inside of your bottle. I.E burnt toast that you cook in an oxygen free oven. Mold your bottle .

👍👍

Number 3 would probably be best for pumping liquid

Offsetting your turbine blades won’t help their speed, it’ll probably help their torque ;)

Better start making a 3D printed compressed air engines or 3D printed internal combustion engines.

Single ball bearing is limiting you here due to weeblewobbles. Some kind of hydrodynamic bearing set (as in also using thrust bearings) might be better eg. foil air bearings, would give less drag, should be 3D printable too (possibly?).

@mitchellstrobbe7779

Жыл бұрын

Could try to make some sort of air bearing, but most likely at this size and power output anything with more friction than the ball bearing would severely impact the output power. Perhaps you could try using a shoulder bolt as a shaft that fits tightly in double stacked small bearings or a brass bushing

@akkudakkupl

Жыл бұрын

@@mitchellstrobbe7779 I think that using regular soda can materials for the foil in the air bearing would work great, could be assembled directly around the shaft, it would need to be shaped somewhat as the commercial ones (probably forming the inner spacer foil into a zigzag might be enough) , would just need to have a two part bearing housing to close around the shaft assembly. Would be cool to see anyway

Im not an enginner but what about sealing, type of bearing, balancing of the turbines, aren't these things have a major effect on the performance

After that, test the impellers.

@algodoomarbleracing

Жыл бұрын

I downloaded the files!

Why not just use a motor to generate electricity which you could measure to get an accurate reading for the turbine power

Next video will be "replacing my impellers with beyblades"

It's interesting how the gap of the offset variants suddenly made almost no impact anymore with higher pressure. No wonder people have to study things like this and run simulations non-stop, this stuff is unintitive as hell...

Bro what size

weeeeeeeeeeeee

I think no 1 would ca8se turbulence no2 would be the more natural but just my thoughts bef9re tue video

"And then we have the original turbine, which I 'optimized' by making it just look like a turbine." That didn't make sense, because you said they were ALL turbines, which means they all _look_ like turbines.

Try a Tesla turbine?

Getting an actually optimized wheel will probably require finding some research papers/theses on turbine design. You might be able to get in contact with indeterminate design, who 3d printed a few turbo compressors based on research papers he found for some tips (kzread.info/dash/bejne/Y5qKtpOom8avdcY.html)

What took so long

Could you please do me a favor and turn off the automatic tile and video description translation. It's just weird to see a german video title with an english video.

@Sciencish

Жыл бұрын

I’m not sure what you mean, did it show up in German for you? Are you in Germany or have your browser set to German?

@thebamplayer

Жыл бұрын

@@Sciencish Yes i live in Germany, but it's pretty annoying, if you see a german title under an english video.

Why not use a Tesla turbine!!

For fucks sake! Use a Tesla turbine for the compressed air side. They're more efficient and more powerful! TESLA TURBINE!!!

really cool video!