More About Leaning During Climb

"Mike Rapoport" wrote in
:

Like you said, you are consuming energy to heat and vaporize the
excess liquid. The energy used to heat the liquid to the boiling
point and then effect a phase change is lost. You are puting liquid
into an engine and having it come out the exhaust at a higher energy
level (hotter and vaporized). That energy came from somewhere.

Agreed. I think we all wound up in agreement on that one. I had
originally thought that Cory was saying that there *was* no heat
absorbed in vaporizing the unburned fuel, and that I was having trouble
accepting. G [True, it's only about 1/4th that of water, but it's
still there.]

But on further msg's back and forth, I think we are in agreement. There
*is*, as you say, a decrease in temperature due to vaporization.

And I will agree that there is probably also (and maybe bigger) a
decrease due to the change in flamefront propogation as the mixture is
enrichened. [Although I question if this is quite correctly
represented. It may give the conductive cooling more time in which to
work, but the exact same amount of energy should be released unless we
slow it up so much that we start shoving flaming fuel out the exhaust
(which can happen). Otherwise, it burns cooler but it burns longer - up
to the still same amount of O2 available.]

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James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
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