将蒙特卡罗法和弯曲光线跟踪技术相结合,研究了各向异性散射性梯度折射率半透明介质层的发射特性.介质层具有镜反射半透明表面和漫射基底面.重点分析了散射反照率和散射相函数对介质层表观方向发射率和表现半球发射率的影响.结果表明对于线性折射率分布的介质层,当散射较为强烈时,表观半球发射率可随介质层光学厚度增大而减小,这种现象与以往研究的半透明体的情况有显著的不同.

By combined the Monte Carlo method and curved ray tracing technique, the thermal emission characteristics of an anisotropic scattering semitransparent medium with gradient refractive index was analyzed. The semitransparent and specular emerging surface of the medium layer was parallel to an opaque and diffuse substrate wall. The influence of the scattering albedo and scattering phase function to the apparent emittance was investigated. The results show that the influence of the scattering to the apparent emission characteristics is important. In the medium with linear refractive index distribution, when strong scattering happens, the apparent emission will reduce with the increasing of the optical thickness of the medium. This phenomenon is quite different from that in conventional semitransparent bodys.