Radiation at certain distance
Radiation at certain distance
(OP)
All,
How to calculate the temperature of air at a certain distance from a heating panel?
I have a temperature in the Nichrome wires of the heating elements and the emissivity.
Im trying to heat a part but need to determine the distance from the panel, how the air temperature decreases with distance..
Thanks
How to calculate the temperature of air at a certain distance from a heating panel?
I have a temperature in the Nichrome wires of the heating elements and the emissivity.
Im trying to heat a part but need to determine the distance from the panel, how the air temperature decreases with distance..
Thanks





RE: Radiation at certain distance
RE: Radiation at certain distance
It can, but only VERRRRY SLOWLY. A typical atmospheric absorption might be 10% over a kilometer
As for heating the part, it'll depend on the absorptivity of the part, as well as the distance, and for sufficiently large distances, the radiation will fall off as 1/r^2
TTFN
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RE: Radiation at certain distance
My point is, I put a thermometer near the panel and I read T1, then I put it at more distance, about 50 cms and I have a T2.
T2 is higher than that of surounding air temp, so this heating comes definitely from radiation.
How to measure or to relate if I have certain KW of power the temp of air at any distance from the panel?
RE: Radiation at certain distance
Apparently, you don't. What's heating up is the thermometer, not the air.
In any case, ~1/r^2, for short distances, there's some error due to your source being extended.
TTFN
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RE: Radiation at certain distance
RE: Radiation at certain distance
You should take a course in thermodynamics.
RE: Radiation at certain distance
I suscribed to this forum with the idea of getting and giving some practical responses to technical doubts in our fields.
The suggestion "You should take a course in thermodynamics" is not appropriate in my opinion. Here there are lots of doubts and I dont see much of hey you should take a course in astrophysics or anything like that.
But thanks anyway.
RE: Radiation at certain distance
You continued referring to "air temperature," even after correction, which suggests to me that you do not clearly understand the physics. If you know all this stuff, then just what exactly is your question?
TTFN
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RE: Radiation at certain distance
As was noted above, radiation pretty much shines right through the air (though not entirely).
RE: Radiation at certain distance
Thx,
RE: Radiation at certain distance
TTFN
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Chinese prisoner wins Nobel Peace Prize
RE: Radiation at certain distance