It is a weｌｌ known fact that apparent directional emittances of the nonmetaｌｌic flat surfaces agree with the calculation results from Fresnelu27s formula， but the emissive property of the nonmetalｌic random rough surfaｃe is not clearly given. In this paper the apparent directional emittances of such surfaces were computed using the same method as the calｃulation of the emittance on the metaｌｌic rough surface，and the apparent directional emittances on the rough surfaces，coated with asbestos tailing mixed paints，were measured. As a result the absolute values and the tendency of the measurements did weｌｌ agree wiｔh the calculations.
展开▼
