|
|
George,
I would like to ask a question about cooling a hot running engine. When the P-51 had to be cooled, I have heard that by allowing the heated exhaust to come out in the opposite direction from the aircraft's motion that the expanded air compensated for the area that it took to cool the engine. Was this wrong? Could an exhaust be designed to use the heated, expanded air to compensate for the cooling drag?
For the Thielert, this is a moot point because we as experimental pilots can't buy the engine but I am interested anyway.
Lorn
From: "George Braly" <gwbraly@gami.com>
Date: March 29, 2007 1:07:15 AM EDT
Craig,
There is “another whole issue” with diesel engines .
.
.
Because the CR is much higher. So the exhaust expansion is more. OK….
But if the CR is much higher then - - so is the peak internal cylinder pressure.
OK… but that means that the bulk internal combustion gas temperatures are a lot higher.
And that means that you get a LOT more BTU’s transferred into the cylinder head.
And, as everybody with some diesel experience is aware - - they tend - - as a result to use rather large radiators.
Because that heat has to be dissipated - - - some way.
HOW ? Either through air cooling through cylinder fins or through a radiator.
.
.
Regards, George
--
Lorn H. 'Feathers' Olsen, MAA, DynaComm, Corp.
248-345-0500, mailto:lorn@dynacomm.ws
LNC2, FB90/92, O-320-D1F, 1,300 hrs, N31161, Y47, SE Michigan
|
|