bigass diesel engine

[dan at angband.org (Dan)]

On Fri, Sep 10, 2004 at 09:51:46AM -0700, Ben Carter wrote:
> 
> What I wondered was, what would happen if they took it up past 102 rpm? 
>  Would it fly apart and take out everything within a mile or two or 
> just keep producing more power.  Sucker must be awfully loud too.

I know the answer to that one... thanks to a thermodynamics of propulsion
course I took years ago.  Once the fuel is injected and ignition occurs, 
it takes a finite ammount of time for the flame to spread from the point
of ignition to the boundary of the combustion chamber.  If you are running
at high RPM with a large diameter piston, the piston may be near the
bottom of the stroke by the time the flamefront reaches it's maximum
spread. So basically, you're burning a lot of fuel and not getting any
additional power out of it, because the piston has reached it's
maximum travel already. This thing has a piston diameter of over 3
feet, so it operates most efficiently at a lower RPM.

Dan

-- 
Life in a box is better than no life at all, I expect. You'd have a chance 
at least. You could lie there thinking, "Well. At least I'm not dead.

		-- Rosencrantz and Guildenstern are Dead