Homemade Jet Engine 4.0 | test run 5

Compilation of the new test runs of the jet engine 4.0. Feel free to also check out the previous videos about my jet engine and subscribe to this channel :)
Link to the PDF document of the calculations: drive.google.com/file/d/1oPCz...
Excel files:
docs.google.com/spreadsheets/... &
docs.google.com/spreadsheets/...

[@Mister_G]

Well done - you are almost there! I think you need to add more gas to get it up to self-sustain speed. Yes, the turbine will get hot, but as the engine accelerates, it will cool down again. They do use a huge amount of gas. You won't see any pressure reading until you are above self-sustain speed. That pressure gauge will show you what you need. Blowing into it will only show 2-3 PSI (0.2 Bar) max which is roughly where you could expect to be at idle.

[@empru4553]

Congratulations! I've been watching since the start, and i'm so glad to see the results of your perseverance. For maybe some recommendations: -have you looked into using the fuel to cool critical parts like the centershaft/bearings, and maybe the exhaust port? -balancing may help a lot. -maybe make the turbine radius slightly larger than the exhaust port? Best of luck!

[@alexandermcalpine]

Your hard work's starting to pay off!

[@pneptun]

it's so hard to design a self-sustaining jet engine! great work, hope you manage to finish it!

[@nicolasm7012]

Nice project. On the other hand, if you want to use gas for the tests, it's a big propane bottle. You will not operate properly with a camping gas bottle. If the turbine wheel is made of Inconel, the reddening is not dangerous, especially at very low revs as is the case in your video. Good luck, you're almost there

[@Danielcraft2002]

for the next tests in my opinion it would be more appropriate to try to install a pump and use kerosene with the engine hot, furthermore due to the high revolutions that a turbine makes the bearings should be constantly lubricated, which from the video does not seem to be done, in fact jetcat uses oil inside the kerosene which first passes inside the hub with the bearings and then comes out to be burned

[@aspboss1973]

First of all congratulations! I am watching from your very first videos on the jet engine. Yes blades do heat up enough glow. But that's for short time. Once it move further from self sustaining, it cools down. I also have problems with gas consumption 😂 But thats the main thing .. so can't complaint about it.

[@TRJx86]

SO close, massive congratulations for getting this close . I couldnt tell you what needs to be changed to get it to self sustain but if I was to point a finger at anything its possibly just the exhaust shape being too large , maybe there is too much vibrations but Ive seen honeywell APUs spit way more sparks out of the exhaust before ' Self clearance' lol

[@burnologist229]

id use zro2 bearing, they are suited better for high temp applications, and they can run dry without lubrication. Id recommend a switch to isopropyl alcohol it burns a bit less hot, and it will allow you to run the engine longer. If you want to take the other route use methanol but be careful to not damage the engine on startup.

[@user-jx9yy7gw1t]

Gut, ja sehr gut!!! Herzlichen Glückwunsch!!!

[@dhirun4]

Congratulations on getting it to self sustain

[@ThirdTyKage]

Not creating vacuum or boost, which is why it’s not running on its own. Your fuel supply needs to be referenced to your engine, electricity via sensors or a mechanical reference. An oil fed bearing system would help a lot. Good progress so far.

[@FX-rh3hd]

Hey, congrulations to your jet engine! I think it will be more easy to self-sustain it if you use kerosene or diesel mixed with oil because the efficiency in these fuels and use the propane for only do the combustion chamber preheating. Also, I would do a bigger compressor intake to avoid very high temperatures in your turbine wheel.

[@IkarimTheCreature]

Auch wenn es momentan nur schleppened voran geht, wünsche ich viel Erfolg bei der Entwicklung. Eventuell wäre ein, Entschuldigung für den Anglizismus, abradable matererial, bei der Verminderung von Leakagen hilfreich. In Kompressoren werden dabei Lacke auf Basis von Kunststoff eingesetzt. Bei der Turbine sind es meistens angeschweißte Honigwabenmuster aus Hochtemperaturmetallen, bei kleinen Turbinen könnte man eventuell mit einer 3D gedruckten Schablone und Galvanik etwas ähnliches Herstellen, das ist aber nur Träumerrei und Spekulation meinerseits.

[@ralphrip6499]

von 6:51 bis 6:56 verliert sie an drehzahl weil du ihr zuwenig gas zuführst, danach erhöhst du die gaszufuhr es ist aber zuwenig um auf leerlaufdrehzahl zu kommen (0,1par). jetzt einen neuen startversuch mit voller gaskartusche.

[@WikWak]

Start it with a leaf blower. It will keep it cooler. Also, you can dynamic balance with a smartphone. Stick weight to a blade, spin and measure, repeat for each blade and look at the results. You can then work out where you need to grind material. 😊 Youre welcome.

[@smad333]

Sounds like it was running fast enough in the first few tests, probably the motor was holding it back and should be taken off at that point? At the end it almost runs at much lower rpm which supports this. Use a much bigger fuel tank, looks like liquifued gas is flowing in sometimes?

[@ByDesignation]

Are those sparks from the compressor blades? If so, I would highly recommend making your own blade balancing tool with an arduino and a couple of load cells. That way you don’t have any wiggle which won’t disturb the intake air compression

[@fjore_starseer]

The turbine produces quite much vibration. For this small size the turbine has to run really fast (>50k rpm) to get stable combustion. If at these speeds something is only slightly out of balance, you will feel it instantly. Through those vibrations energy gets lost by flexing and the resulting leakage.

[@michaelnorrgren747]

Very nice, nice progress. You arr doing so good. When you get the revs up, Whyred not trying to inject kerosene instead of using propane, doesnt that give you a more stable engine?

[@mitubachiflight]

I think installing a Bell mouth on the air intake will make it much more efficient.😀

[@ChilligDiggi]

Vielleicht gibt es eine einfache Lösung. Du brauchst mehr Luft/-druck. Es sollte sich ja eigentlich selbst mit der Luft abkühlen. Und mehr Druck bedeutet auch Selbsterhaltung. Bau vorne ein 3D rahmen dran und und vielleicht noch eine etwas größeren Intake Fan. Das ist wirklich so minimal intensiv, das es sich nur lohnen kann es auszuprobieren… ✌🏻🙏🏻

[@metalugiamirante1214]

Top 👏👏👏

[@maiwandtakoor989]

Recheck your diffuser. Last time I saw it in your assembly videos, it didn't have any diverging parts on the front.

[@marcnavarro6297]

Le roulement à billes après la chambre de combustion est une erreur. Le compresseur centrifuge est sous dimensionné par rapport au diamètre de la turbine qui absorbe toute l'énergie. La compression est-elle suffisante, j'en doute.

[@alex-mzlzl]

You should use much more gaz or kerosene injection, you have so much comburant for little fuel

[@sebas5688654]

Ну, почти получилось. Надеюсь, скоро будет нормальный старт.

[@Jappmannen]

You can clearly hear that the engine has a bearing failure so why try again and again and again?

[@UlrichVIII]

it ran! not efficiently, but it ran on its own nonetheless!

[@mruniverse5704]

Noooise. Try to heat up gas a little with warm water

[@anmau2003]

Du brauchst einen richtigen Diffusor! (mit“Keilen“) sonst gibts nie Druck.. Einspritzung um 180 grad drehen. Lager muss mit Feder vorgespannt werden … melde dich mal ! Dann kann ich dir meine 800N Turbine zeigen, ist ein Eigenbau 🎉 beste Grüße

[@Rastamaxa100]

give me the contact of these people, I will explain what they need to do to start their engine, who knows where to write???

[@grah55]

I honestly at this point don't think you understand the point of a jet engine and have a mindset of the tolerances required to have it be efficient and self sustaining. That said, alot of work still goes into what you have done, and thats nothing to ignore or deny. Considering the following: Your power source is your liquid fuel, and the thrust is what you're after. What you have right now looks like nothing more than a flame thrower. Where does your fuel come out? How does it burn? You can't just have an essential lighter inside of a big chamber with alot of gas and an explosion happening with alot of turbulent air. The whole burn process needs to be extremely well controlled: The burner pipes need to have extremely tight tolerances and create makeshift fuel to air burners. The fuel pours in through the feed line and comes out at all the pipes evenly and then is evenly ignited at all sources. Low speed moving air supplies the entire combustion chamber with fresh air. The exhaust pressure causes the turbine to spin, which drives the compressor, which brings in more air. But just because you have more air doesn't mean you don't need more fuel. And yes, your rotational parts still have horrible problems as evidence via how quickly the whole thing winds down to a halt. It needs to be so smooth that the blowing on it with air (not even compressed air, just the air from our lungs) can move the rotational parts of an engine that small. Why? Because why lose all or any air-to-rotation power change or rotational_power-to-air speed change to friction. You have alot to fix but if you fix all of the above, you wont even need that spin starter. You would just need to finger rotate compressor, light the burners up and then watch the whole thing accelerate on its own. I'm serious. This is all that is required. Best of luck fighting out the whole bearings issue though, that will be tough, and you do need to make sure it's perfect/measured perfectly, all sources of friction removed.

[@SohagMahmud-b1s]

Hello how are you