Re: [DML] Engine cover screens - necessary or not?

[Peter Lucas <lucas@xxxxxxxx>]

On Feb 24, 2013, at 3:47 PM, Martin Gutkowski <martin@xxxxxxxxxxxxxx> wrote:

> The average engine temperature will rise but the energy level *at the point of shut off* won't. Here's why - including the surrounding air, you're assuming the engine to be a closed system and it isn't. When running the system includes the coolant circuit, when switched off it becomes just the engine, therefore the energy that would have been transported away via forced convection in the coolant content of the engine suddenly becomes part of the closed system that is just the engine and it must now reach thermal equilibrium by dissipating heat through free convection and radiation to the air around it. You've taken a large system in dynamic equilibrium and suddenly switched to a smaller system which will then move to a static equilibrium. In short, it's not a simple question - and I agree the hottest parts of the engine will not get hotter, but many sensitive parts of the engine, eg heads and gaskets, block etc will.

Well, I now agree with everything you say except for the first sentence of the above paragraph, which probably means we are now arguing about definitions.

I hereby self-moderate myself out of this discussion on the basis of lack of DeLorean content.

--Pete Lucas
VIN #06703





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