View Single Post
  #1  
Old July 17th 05, 05:48 PM
Don Stauffer
external usenet poster
 
Posts: n/a
Default

mastic wrote:
> "Sport Pilot" > wrote:
>
>
>>Here is an animated link showing the differances of the Otto and Diesel
>>cycles.
>>
>>http://www.ulb.ac.be/sma/testcenter/...osedcycle.html
>>
>>Notice the near instant burning in the example gives very nearly a
>>constant volume, in actual practice some compression is going on at
>>this time.
>>
>>Also during a Diesel cycle it is hard to maintain a constant pressure,
>>it would actually drop off, especially near the end of the down stroke.

>
>
> But both are still otto cycles.
> If you think the fuel burns instantly in a spark engine remove the
> exhaust manifold and run the engine, observe the flame exiting the
> exhaust port.


Indeed, if it does burn "instantly", that is detonation. However, it
burns more rapidly in a SI engine than in a true Diesel cycle Diesel. In
fact, it is astonishing to me how fast one can turn even relatively
large SI engines, such as Formula 1 car engines. Is there no limit :-)
Ads