固体表面定向发射率的计算模型与试验研究*

Research on the Directional Emittance of Solid Surfaces

根据数值迭代求解固体的光学常数ｎ，ｋ．首先应用经典的电磁场理论对光学表面在远红外波段的定向发射率进行了计算，然后将实际表面模化为由各种不同倾角的Ｖ槽按正态分布随机组成的表面．定义正态变量的数学期望值为该表面的粗糙度，结合经典的电磁场理论，建立了一个定向发射率的计算模型．实测表明，该模型不仅适用于光学表面，也适用于表面粗糙的非金属表面．

Based on the classical electromagnetic theory, the directional emissivity of the optical surface has been calculated with its optical constants n & k. A statistical model to calculate the directional emittance of the real surface is successfully built with the assumption that the real surface is formed by multiple Vgrooves whose walls' slopes are taken to have a normal statistical distribution.The experiments show that this model can be used not only on the optical surfaces, but also on the rough nonmetal surfaces.