alternative engines, now Hemi

[William T Wilson]

On Fri, 21 May 1999, Gary Derian wrote:

> Engine research using ceramics is headed toward an adiabatic engine.  
> That is one which needs no cooling system.  This keeps the fire hotter
> during the power stroke since no heat is absorbed by a cooling system.  
> I would think this would actually increase propensity for detonation.

It doesn't, necessarily, because the nice thing about an adiabatic engine
is that having a hot fire during the power stroke hasn't got anything to
do with the temperature inside the cylider during the intake/compression
stroke.

If the engine needs no cooling system, then that means that heat isn't
building up inside it (which is good, because all that energy can go into
useful work instead of out the radiator).  Since heat isn't building up
inside it, that means all the generated heat is getting blown out the
exhaust, and the inside temperatures are nice and cold when the next
charge comes through.

Ceramics have extremely high tolerance for heat, and relatively low heat
transfer rate.  Which means that heat generated in the power/compression
strokes doesn't have *time* to get transferred into the engine itself.