Here's a video of the Jet Engine made with a car turbo charger - runs on propane. The neighbors love me:)



- No plant pots were harmed during the making of this movie :)

Some technical explanations



Here's the direct youTube link

and a test run to 13lbs of thrust



Here's the direct youTube link

Here's a picture from a museum showing a burn-can / mixer box (upper left). A similar design is used in the jet.



In its final resting place



Full size image here

And under some funky lighting

Here are some replies to comments on YouTube..

honeybunchickens what do you mean by injecting water. In what why possible. Your hoping that the water is going to evaporate before it reaches the combustion stage. You need to evaporate the water like you would with liquid fuel. having evaporating nozzle lets say like a 3.5 gph at 80 psi at a 60 degree spray pattern towards the intake, naturally air teps cool down when touching water. similar to how a EVAPORATOR COOLER works

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The water is not actually "injected" into the intake, it is sucked in by lower intake tube pressure at high engine power. It is sprayed into the intake via two atomizing carburetors (see coffee table picture) that suck water up from the outside pan (the bottom transmission pan). This cools the in-coming air by evaporation as you say, and when the water boils after compression and in the combustion chamber, it adds extra gas expansion volume and mass flow. Cooler compressed air temperatures, allows more heat to be added to the gasses before passing the gasses to the turbine without melting the turbine blades, resulting? in higher thrust output.

AGEOFMANGAS Have you ever considered enclosing the hot turbine and cone in a water jacket to form a crude boiler? This steam would run through a tube to be injected just downstream from your fuel burner and just before the turbine. It would serve several purposes. 1) keep the turbine blades from over heating. 2) Provide more thrust using waste heat. 3) Provide moisture that will continue to expand as it exits the exhaust nozzle giving something like an after burner effect only with steam instead of fuel.

Reply A more efficient use of water is to inject it into the intake.
This cools the compressed air temperature allowing more fuel to be injected before reaching the turbine blade max temperature, giving more thrust. Then reduce waste heat by using a turbo insulator jacket. cont... #

AGEOFMANGAS

end of your reply says "cont..." I don't know how to get to the continued part but I will reply to what I read. The water injection to the compressor sounds sensible but how would an insulator jacket "reduce" waste heat? the heat in the turbine housing only has two places to go in that case 1( through the insulation 2( out with the exhaust. In either case you are not gaining anything from it. the boiler would allow the energy to be dumped upstream of the turbine for pwer & coolin

Reply

Yes - issue is youtube posting - got an 'error' on the second part so will try again

If you look at the still picture at siliconproductions jetengine jetengine.html and you will notice two water carburetors on the air intake tube for water injection, that activate automatically near max thrust.

Thrust (lbs) = 2 x (Exhaust Back Pressure in psi) x Nozzle Area (sq. inches) The hotter the exhaust, the larger the nozzle area you can have for the same exhaust back pressure. This is how an after burner creates extra thrust. When the after burner is on, you increase the nozzle area. You want the heat to stay in the exhaust gas to create back pressure, NOT be radiated as waste heat externally.

In the above equation, the back pressure is the pressure measured AFTER the turbine exhaust NOT the compressor pressure. It will only be a few psi at most for a typical turbocharger jet engine. In a jet engine, unfortunately efficiency and power move in opposite directions ;-( You need a LOT of water injection to increase thrust. I found water injection quickly creates horrible rust issues in the turbine housing.

Going to try and explain that again... Thrust (lbs) = 2 x (Nozzle Back Pressure in psi) x (Nozzle Area in sq. inches) Where the "Nozzle Back Pressure" is measured in the tube after the turbine but before the smaller diameter nozzle. It will only be a few psi for a small turbocharger at most before the turbine blades get too hot. Nozzle back pressure is NOT to be confused with the compressor pressure.

So, looking at the above equation, you can see that you want to keep the heat inside the turbo using insulation, because the hotter the exhaust, the more the gas is expanded, so the larger the nozzle area you can have for the same nozzle back pressure. A larger nozzle area for the same nozzle back pressure gives more thrust. This is how an after-burner creates more thrust also. In a standard turbo-jet engine, unfortunately efficiency and power move in opposite directions ;-(

I also found water injection quickly creates horrible rust issues inside the cast iron turbine housing. In a stainless steel housing this would not be an issue.

DanielAlanJones

why did you install a rheostat on the electric blower?

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The actual velocity of a normal fuel/air flame front is pretty slow - a few tens of mph. If the air/fuel mixture is coming out of the rear nozzle faster than this, the flame front cannot pop back into the combustion chamber. Put very simply, you will not be able to light up the jet from an external ignition source if the leaf blower was blowing mixture out of the nozzle at 100 mph.

potsmoker5000

Would water methanol injection help with EGT in this case?

Reply

In theory, yes.

Also, anything that cools the intake air will allow you to use a higher percentage of the available oxygen to burn more fuel, before the turbine reaches it's maximum operating temperature limit. ie you should be able to get more thrust from it. Even a cold winters day will help you get more thrust than in the summer.

If you look carefully at the picture of the jet, now in my coffee table, at the following link: www.siliconproductions.com/jetengine/jetengine.html (the last photo)

You will see two home made carburetors for water injection at right angles to the air intake tube. These pick up water from the tray below when the suction from the intake tube is sufficient at higher powers.

A better design would be to use a high pressure pump and small injector nozzles to get fine atomization. The carburetor design doesn't atomize well enough so you get intermittent steam rings blown at high velocity out the back as the droplets enter the combustion chamber. Fun to watch though.

potsmoker5000

Okay now that makes me wonder would intercooling do anything?

reply

Difficult to answer properly in the space available. But I will try. Inter-cooling on a jet AFTER compression is no good, since all the inefficiency of the compressor has already taken place, as the compressed air slows down in the "snail shell" where the high velocity air at the blade tips is converted to pressure in the case. This is where most of the inefficiency comes from.

If you use an inter-cooler, what happens next is that you just heat the air up again in the combustion chamber, so you just wasted energy cooling it down. Don't get confused by what happens in turbo-charged car engines.

What you need to do is have cold dense air going IN to the compressor. The temperature rise from compressor output air to turbine input air given to it by burning fuel in the combustion chamber, is what adds the power. The colder the air in, the colder is the compressed air so the more heat you can add to it before you melt the turbine blades, so the more power you can get out.

If you use liquid propane fuel and evaporate it in a heat exchanger to cool the intake air, you could in theory reduce input air temperature by approximately 10 centigrade. Add highly atomized water also such that it evaporates before being compressed and you go cooler still. A long smooth walled air intake evaporation tube is what you need. Angle the walls by around 7 degrees, it will be even more efficient.





13thbiosphere wrote

" can you please run a turbine on hydrogen/oxygen

perhaps you could get a hydrogen generator and test the concept

I guess NASA have done this before

But I would like to see a micro setup

Could you put a wind turbine behind it and see is you can generate some electric energy

It would be fun to see electric energy breaking water then a wind turbine also splitting water

Perhaps 50% of the fuel could come from the wind turbine

Does the idea sound like fun?

who built you turbine? can you film the process? "



Reply:

You can run a Jet on anything that generates enough heat.

So yes, you could use electricity to generate hydrogen and use that as fuel. You will need about 100,000 watts of power even for this little jet. It would be more efficient to use the electricity to generate the heat inside the burn can directly from high power heating elements. About one hundred 1 kilo Watt heater elements connected together should do it. Now you realize just how much power is stored in fossil fuels ! You will need to make a large burn can to put all the heating elements in !

If you want to get really crazy, you could also use a 30 foot by 30 foot solar concentrator mirror as a heat source.

We did do an experiment with an augmenter set up consisting of a 12 inch diameter, 4 foot long pipe and a large cooling fan to generate electricity from the jet.

The power from the jet was sufficient to blow the heavy fan clean over. We even have that on video I think. Quite funny.

The turbo-charger itself is made by Garrett.



hawkeyeriggs5000 wrote

So I was watching these videos one night, and saw that you got the same turbo I got! Best thing that ever happened to a mid-80's chrysler!

Anywho, I was wondering about a couple things:

What size fuel orifice did you use? I'm going to try a 1/16" size. Is that too big? Small?

Did you regulate your fuel flow with a BBQ regulator? I did, and think it's not going to give enough.

Ging to start it for the first time tomorrow, if it will run.

Thanks, and have fun with it!



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I cannot recall exactly what size propane jet I drilled, but I have a feeling it was 1/16th of an inch also. The size of the jet is not too important (so long as it is big enough. The flame cannot go back up your propane supply line if there is no air in it to support combustion.

I used an acrylic gas flow meter which had an integrated valve on it that I used for the throttle. The maximum flow was 4 CFM which is plenty for that turbo. About 2.5 CFM is all you should need for max power at which point my decibel meter read 120dB from about 3 feet away !

If you use a modern propane tank safety connector, chances are you won't get this kind of flow. Buy the old style brass bottle connector that uses the inside, left handed thread of the bottle. These are much better. See if you can find an acrylic valved gas flow meter for the throttle. Mine looks similar to this one made by King Instrument

http://www.instrumart.com/Product.aspx?ProductID=10153

I got it from a semiconductor/electronics industry orientated surplus store. Maybe school scientific supplies have them ?

mike