Hot Air vs Cold Air

["Marvi, Maurice" <MMarvi@domain.elided>]

In general, at atmospheric temperature, hot air has less O2 per
liter/Cubic_foot/breadboxes (pick your unit), but if you increase the
pressure to gain parity in O2 content, hot intake air will be more efficient
because it will take less energy from the burning fuel air mixture to waste
in the exhaust.

I remember reading in the 80's about how Smokey Yanuck (sp?) tried to create
an adiabatic engine. He heated the intake charge with the exhaust, and used
a supercharger more as a check valve than a pressure pump. Of course he ran
into extreme detonation problems which he would ignore when noted by the
journalist from one of the car mags (I forget which one). Considering the
combustion temps, NOx production must be huge as well.

Lets face it Mr. Yanuck isn't known for playing by the rules, and the engine
he showed may not have been all he said it was, but with improvements in
computer controls, materials and fuels the adiabatic engine may be ready for
another try.

Alfa Content-

The recent AlfaOwner has an interesting Note Brevi by Pat Braden on internal
combustion. He mentions the need for a new paradigm, maybe the adiabatic
engine is the way to go. Maybe our resident Automotive engineers will pipe
in.

Maurice Marvi
'87 spider 
New AROC member
Lapsed SAE member (ended up working in insurance, ahhhhhhhh!)

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End of alfa-digest V7 #866
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