Combustor design and red hot turbine and turbine housing.

[azwood]

Nov 26, 2018 21:30:35 GMT -5 racket said:

LOL, evaps.........vapourisers , same same , technically correct to call them vapourisers , even though they evaporate the fuel , I'll still call them by both names , I think evaporators is a term more easily understood , whereas vapourisers has other connotations these days.....................neither of them fully turns the fuel into a "gas" , some liquid is still ejected from their outlets ..

I just pulled the 12/118 engines flametube apart and its "evaporators" are still fairly shiny/silvery in parts and don't appear to have been unduly scorched by the combustion process surrounding them .

Where do I get a spray nozzle from I just want it to start without LPG so it won't need to flow lots I was thinking if it was small enough I could Leave it running so it didn't get cokeing I think that what they call it.

[racket]

Hi Aaron

Check the phone book for a local supplier of fuel burner nozzles , I'm certain theres a number of them in Melbourne for some free info :-)

Cheers
John

[azwood]

OK will do I have some misting nozzles here but there brass I thought they might melt.

[rickw]

I figured out how to find leaks on my engine. Run liquid fuel. yikes. so how do you seal threaded areas on the combustor cap?

[azwood]

Nov 28, 2018 20:58:41 GMT -5 rickw said:

I figured out how to find leaks on my engine. Run liquid fuel. yikes. so how do you seal threaded areas on the combustor cap?

There's a few good compounds out there for the maybe high temp rtv silicone

[racket]

Brass is OK as long as theres fuel going through them to keep them cool , but don't run just on LPG as its flame could soon melt the brass .

Is the spray nozzle just for experimenting or do you want to switch over to liquid, and only use the gas as a pilot light ??

[rickw]

I bought a stainless steel nozzle from McMaster-Carr and it works great.

[azwood]

Nov 29, 2018 0:27:32 GMT -5 racket said:

Brass is OK as long as theres fuel going through them to keep them cool , but don't run just on LPG as its flame could soon melt the brass .

Is the spray nozzle just for experimenting or do you want to switch over to liquid, and only use the gas as a pilot light ??

I planned to use the brass jets for starting they make a very fine mist.then just leave it running after I switch to the evaps just so they don't burn out.as long as I have 60 odd psi going to them they won't stop when I wind it up ofcorse I'd need a good filter because they block easily.

[rickw]

Ok so I'm running on diesel fuel and all seems good accept the combustor end cap is getting red hot. If I put a boost gauge on will that keep me relatively safe on engine speed if I keep the pressure under 30psi?

[racket]

Hi Rick

To help cool the combustor end cap you'll need some holes drilled in your flametube wall at the very top so as to blow "cool" air across the cap underside , if need be you can blank off a row of your Primary holes and "shift" them to the very top, for cooling first, then adding into combustion airflow.

Without knowing a lot more about your turbo I wouldn't advise going past 25 psi P2 , but if the air temperature coming from your compressor indicates good efficiency and no chance of it running in the choke region at poor efficiency and relatively "high" rpm , then and only then would it be safe to increase P2 .

Cheers
John

[rickw]

Thanks John