Blackbody globe thermometer
Blackbody globe thermometer
(OP)
Needing some quick mean radiant temperature readings, I've made a quick-and-dirty blackbody globe thermometer from a cheap aluminum tea kettle.
Not being an actual globe, I suppose it is actually an aspherical globe thermometer. My aspherical globe thermometer is in fact a cylinder.
The formula provided in the ASHRAE handbook to obtain MRT from the globe thermometer reading contains a term for the globe diameter.
What should I use as the value for this term with my cylindrical thermometer?
My thought would be use a value of D for a sphere of equal surface area as my cylinder.
Not being an actual globe, I suppose it is actually an aspherical globe thermometer. My aspherical globe thermometer is in fact a cylinder.
The formula provided in the ASHRAE handbook to obtain MRT from the globe thermometer reading contains a term for the globe diameter.
What should I use as the value for this term with my cylindrical thermometer?
My thought would be use a value of D for a sphere of equal surface area as my cylinder.





RE: Blackbody globe thermometer
Maui
RE: Blackbody globe thermometer
1> The radiant component won't match a sphere. You may have to take each surface and independently determine the view factors.
2> The convective component would seem to be best kept as a cylinder
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