紫外波段多分散系气溶胶散射相函数随机抽样方法研究

Study of random sample scattering phase functions of polydisperse atmospheric aerosol in ultraviolet band

基于电磁散射与辐射传输中的基本理论,对紫外波段霾尺度范围内满足特定分布的多种气溶胶粒子的散射相函数进行了研究.提出了一种直接随机抽样拟合散射相函数的方法.比较了H-G相函数、改进的H-G相函数及随机抽样拟合的相函数与多分散系Mie相函数的偏离程度.数值计算了不同相函数拟合方法对应气溶胶的传输特性.计算结果表明,相函数的准确模拟计算对于蒙特卡罗方法等辐射传输问题的解决具有十分重要的意义.

Based on the basic theory of electromagnetic scattering and radiation transmission, the scattering phase functions of various kinds of atmospheric aerosol with special distributions in typical UV band are presented. A direct sample method has been used to simulate the discrete polydisperse Mie phase functions of haze aerosol. Comparisons are made between the Henyey-Greenstein phase function, the modified Henyey-Greenstein phase function, the direct sample phase function presented in this paper and the polydisperse Mie phase function. The influence of different scattering phase function simulation methods on radiative transfer properties has been studied by using the Monte Carlo method. Numerical results showed that the rigorous simulation of scattering phase function is of importance in radiative transfer problems.