Question

Why emissivity of a rough surface is more?

Answer 1

I think that you should consider first a measurement of the roughness of the surface. Typically a rough surface acts like micro blackbody cavities, enhancing the total emissivity of the surface. As soon you have an idea of the magnitude of the "valleys" and "hills" of the surface, you may be able to correlate it to the wavelengh. I know this will not be simple, but I think it is a good starting point

Answer 2

heya....

I think that you should consider first a measurement of the roughness of the surface. Typically a rough surface acts like micro blackbody cavities, enhancing the total emissivity of the surface. As soon you have an idea of the magnitude of the "valleys" and "hills" of the surface, you may be able to correlate it to the wavelengh. I know this will not be simple, but I think it is a good starting point.

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