大气气溶胶粒子散射相函数的数值计算

Numerical calculation of phase function of atmospheric aerosol particles

大气气溶胶粒子作为大气电磁环境的重要组成成分之一,在紫外、可见到红外波段内严重影响电磁波的传输特性。散射相函数是研究气溶胶中电磁波传输特性的一个重要参量,依据粒子电磁散射理论,数值计算了球形和椭球形气溶胶粒子在红外波段给定波长入射时散射角余弦的一阶矩,给出了气溶胶粒子HG相函数和改进HG*相函数的数值结果,并将球形气溶胶粒子的这两种相函数和Mie散射相函数进行了对比。结果表明:随着波长的增加及气溶胶粒子尺寸参数的减小,HG*相函数能更好地体现红外波段气溶胶粒子的散射特性。相函数的准确计算可为研究气溶胶中红外激光的传输特性奠定基础。

Atmospheric aerosol particles,as one of the important ingredient in atmospheric electromagnetic environment,can catastrophic influence the transfer characteristic of electromagnetic wave from ultraviolet and visible light to infrared.The scattering phase function is an important parameter for studying transfer characteristic of electromagnetic wave propagate in atmospheric aerosol.Based on the electromagnetic scattering theory of particles,the first moment of cosine scattering angle of spherical and ellipsoidal aerosol particles under infrared band was calculated,the numerical result of HG and HG＊ phase functions of aerosol particles changed with wavelength and scattering angle,and the comparison of both the two functions of spherical aerosol particles and Mie phase function were given.The result shows that HG＊ phase function can describe the scattering property of aerosol particles better under infrared band with the increasing of wavelength and decreasing of size parameter.The rigorous calculation of scattering phase function has an important significance,and it can establish foundation for studying transfer characteristic of infrared laser propagate in atmospheric aerosol.