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<DIV><FONT size=2 face=Arial>All,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>It appears to me that the effect of ambient
conditions on a TLUD-ND operating at low power is quite complex. The
excellent responses to this thread have pointed to several
possibilities.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>1. The heat loss from the stove and pot to
the atmosphere is reduced because the temperature difference is less.
(Thank you Prof Lloyd)</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>2. At higher ambient temperatures the primary
and secondary air is effectively pre-heated before it enters the stove.
This leads to a hotter pyrolysis front, faster wood gas production, and a larger
secondary flame. (Thank you Crispin)</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>3. Higher ambient temperatures may be
accompanied by higher humidity, which reduces evaporation from the pot.
How does higher humidity effect the flame? (Thank you
Crispin)</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>4. If I might add another, higher ambient
temperatures are often accompanied by higher barometric pressure, which
would increase the vaporization temperature so the pot will heat up
slightly. It will also increase the vaporization temperature of the
volitiles in the fuel, slightly increasing the fuel temperature. This may
seem very small, but the stove operates on buoyancy pressure differences
measured in single digit Pascals, so a change in barometric pressure may be
more than the pressure differences that drive the stove.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>The total effect of a combination of these could be
considerable.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Kirk H.</FONT></DIV>
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