On Fri, 12 Feb 2010 02:29:18 +0000 (UTC), David Lesher
wrote:

cavelamb writes:


Check the marine engines. We do this all the time to keep salt water
out of the engine cooling jackets.

But those are for liquid-cooled engines; this is not one.

But they do cool the exhaust as well. There are water jacketed
exhausts with two coaxial pipes. The exhaust runs thru the inner pipe
and water circulates in the space between the two pipes.

Then there are water injected exhausts that have a sort of upside-down
u-trap after the engine's exhaust manifold. Water introduced into the
exhaust at the downstream side of the trap cools the gases and the
plumbing enough that rubber hose can be used beyond that point.

The water jacketed system would be the most practical for reclaiming
exhaust heat.

--
Ned Simmons