Question for Don Fairchild or others

[niles500]

Don - would it be theoretically possible to design and build (unlimited budget) an approximate 350 cc single cylinder two-stroke water cooled turbo diesel that;

1) Could develop approximately 20kw continuously operating at fixed rpm in the power band at peek (not maximum power) thermal efficiency?

2) Could maintain an EGT of 900 to 1100 degrees after the turbo?

3) Would consume about 1/2 gallon of fuel per hour ?

4) Would meet EPA and Carb standards with proper exhaust?

What efficiency percentage of btu's do you think is possible?

Thanks in advance

[Zeroclearance]

An engine 3 times that size would be difficult to provide 20KW as a four stroke..   A two stroke would need to run on a lot of boost and fuel to make 20KW..   It would be tough for a 350CC 2 cycle engine..   Go and look at the Kubota EB300..   I think that is can only put out 4500 watts.  

20Kw = 26.8HP..   That's not counting the thermal loss.   Plus the HP loss belts, drivetrain, alternator, supercharger if needed.

[TomC]

350cc is only 5.73cu/in. On gasoline, you'd be good to get a peek of 15hp out of this engine. Detroit/Delco made a 20kw genset that ran refrigeration units on railroad refer cars. That was a 2-71 (142cu/in) running continuous at 1800rpm for sometimes years at a time.  Good Luck, TomC

[luvrbus]

TomC, Santa Fe ran the 51 series (2 cylinders 102 CI) in the 50's for years on their refrigerated cars I still see a couple setting at the Needles yard  

When the yard master finds out if he can sell me one I am going to play with it most people never saw a 51 series with no exhaust valves neat old engines

[Lee Bradley]

All correct about the long lived Detroit/Delco but they ran at 1200 rpm. That is how they ran that long.

http://www.hardydiesel.com/diesel-generators/detroit-1200-rpm-diesel-generator-22-kw.html

[TomC]

The 51 series was interesting-made in either 2 or 4 cylinder. With just ports. Had a blower, and a camshaft just to power the unit injectors. Loud mothas though. Still-fun to play with.  Good Luck, TomC

[Low Class]

Tom, you must be useing that new math, "350cc is only 5.73cu/in".

I always thought a 350cc was a 21 incher.   

[Utahclaimjumper]

 Its your low class thinking that's wrong,,, the magic number is 61,, as in 61 cubic inches in a liter or 1000CC.>>>Dan ( An 8.3 Cummins ISC engine is (8.3 X 61 = 506.3 CI) ( An 8V71 Detroit is 568 CI)

[TomC]

OOPS-went the wrong way with the calculation-yes it is a 21.39cu/in engine. Considering a high powered 6V-92TTA can put out 435hp for fire truck rating-if we take 435hp and divide it by 552cu/in and multiply it by the above 21.39cu/in, we'd have an engine that puts out 16.85hp. Since that is only at 2100rpm-a 350cc engine could easily do twice that rpm-so around 33hp would be my guess out of a 350cc 2 stroke Diesel engine.  Good Luck, TomC

[TomC]

At 33hp (24.75kw) you'd be consuming about 1.7gal/hr. Good Luck, TomC

[niles500]

Oops it's peak not peek - I should read first before I hit post

ZeroC - the EB is naturally aspirated 4-stroker so I wouldn't expect it to be high output, also I need to clarify I am talking about 20kw at the crank I've already considered the inefficiencies downstream - The only things driven besides the shaft will be water and oil pump - thanks for your input

TomC - and that 6V-92 could probably be pumped up in a marine application to 600+ HP at the expense of engine life - I need continuous output, low fuel consumption, light weight, reliability and reasonable longevity of the mill - thanks for your input

Luvr - You must still be doing the math - go ahead and hazard a guess

[niles500]

TomC - current diesel technology has fuel efficienies of between approimately 38% to 55% in general - there are many variables to be considered when figuring the brake specific fuel consumption (BSFC) which is why my question was theoretical - thanks for your input

[TomC]

As to continuous turbocharged engines-a Detroit 6-71TA has a continuous rating of 230hp at 1800rpm (165hp non turbo'd).Take 230hp and divide it by 426 and multiply it by 21.39 and you'd have 11.5hp at 1800rpm. I would safely say a 350cc engine could happily run at 3,600rpm all day, so double the horsepower to 23hp (17.25kw) at 3600rpm. Good Luck, TomC