An Improved Small-Angle Approximation for Forward Scattering and Its Use in a Fast Two-Component Radiative Transfer Method
An Improved Small-Angle Approximation for Forward Scattering and Its Use in a Fast Two-Component Radiative Transfer Method
复制标题
DOI：
10.1175/jas-d-16-0278.1
复制
发表时间：
2017-05
影响因子：
3.1
通讯作者：
Bingqiang Sun;G. Kattawar;P. Yang;E. Mlawer
中科院分区：
文献类型：
--
作者：
Bingqiang Sun;G. Kattawar;P. Yang;E. Mlawer
摘要 矢量辐射传递方程被分解为两个分量：前向分量和扩散分量。前向分量通过小角度近似进行解析求解。前向分量的解成为漫射分量的源。在本研究中，使用连续顺序散射方法求解漫反射分量。介质散射辐射的强各向异性仅限于给出半解析解的前向分量；因此，一旦前向散射峰被去除，漫射分量就会作为散射角的函数缓慢变化。此外，由前向分量引起的对漫射分量的影响可以通过包括前向分量的广义球函数展开的低阶来解释，甚至可以用狄拉克δ函数代替。因此，可以显着减少计算量。目前的双组分方法是...
AbstractThe vector radiative transfer equation is decomposed into two components: a forward component and a diffuse component. The forward component is analytically solved with a small-angle approximation. The solution of the forward component becomes the source for the diffuse component. In the present study, the diffuse component is solved using the successive order of scattering method. The strong anisotropy of the scattering of radiation by a medium is confined to the forward component for which a semianalytical solution is given; consequently, the diffuse component slowly varies as a function of scattering angle once the forward-scattering peak is removed. Moreover, the effect on the diffuse component induced by the forward component can be interpreted by including the low orders of the generalized spherical function expansion of the forward component or even replaced by the Dirac delta function. As a result, the computational effort can be significantly reduced. The present two-component method is v...