I'm having trouble with the cooling requirements of this tube.
Specs say 350 W requires 40 m**3 per hour. At 1.2 kg.m**3, that's
52 kg/hour air, squeezed through a 200mm**2 heat exchanger 'duct'.
If air were not compressible, this would translate to a 200km/hr
air stream! I did calculate the temp rise and IIRC(notes at work)
the exiting air will be 24 degrees C warmer than the entering air
for this mass flow and transfer of 350W.
The volume of the heat exchanger in which this temp cahnge takes
place is fixed. So, the increase in pressure resulting from the
heat gained looks pretty easy at first glance. The entering air
is compressed so undergoes some adiabatic heating as well which
may have to be accounted for??? What about the friction from the
heat exchanger??? Is this the same order of magnitude as the
pressure change from heating by conduction?
Does the pressure change(increase) in the heat exchanger get me
within 10 to 20 percent of the I need when specifying a blower?
Never having worked with this stuff, I just don't have a 'feel' for
the relative contributions to the back pressure...
-bob
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