[Vwdiesel] Re: [Audi-VW-Diesels] EGT temps revisited

[maded]

Nate and all,

Yes, the temp drop is from taking out energy from the gas stream. Air cycle
chillers work the same way, except the exit air is cold, real cold.

I remember reading a Scientific American article years ago where a guy
devised a compound diesel engine to extract more energy out of the fuel
(diesels have way more air than used in combustion, that air has energy).
He had worked very hard and finally engineered a solution but the
complication was not worth the trouble.  This was years before turbos so he
ended his article saying something like..."of course today we get the same
result in a much more straightforward way, the turbocharger."


--
Ed Lowe, Seattle
82 Westy diesel upgrading to 1.9td
85 Golf diesel
92 Cabrio
97 Passat Tdi
> From: Nate Wall <nwall at opei.org>
>
>
> What causes the temp drop?
>  gases expand as they pass through the turbo, giving up
> energy (doing work) against the turbine. As that expansion occurrs, the temp
> drops.
> Remember old steam locomotives? Some of them use a smaller cylinder under the
> primary one to expand the steam a second time (the first cylinder exhausts
> into
> the second) on each set of drive wheels to get greater effeciency.
>
>