基于蒙特卡罗方法的烟幕透过率计算与分析

烟幕透过率是表征烟幕干扰性能的重要参数。以等效粒径为0.1μm的石墨为例,就不同形状的石墨粒子组成的烟幕,基于蒙特卡罗方法对烟幕透过率进行了数值计算。利用Mie散射理论和离散偶极子近似(DDA)方法分别计算了球形粒子、椭球形粒子和圆柱形粒子对1.06μm波长的入射光单次散射的消光参量。对于入射光在烟幕中的传输,建立了蒙特卡罗模拟计算模型,利用MATLAB语言编制了相应的计算程序,给出了不同纵横比的椭球形粒子和圆柱形粒子相应的烟幕透过率计算结果,并和等体积球粒子相应的烟幕透过率进行了比较分析。结果表明:透过率与烟幕中粒子形状、粒子数密度、入射光的入射角度及烟幕厚度有关,粒子形状越偏离球形,对应透过率越小。

Numerical calculation and analysis of transmittance of smoke screen based on Monte Carlo method

The transmittance of smoke screen is an important parameter for interference performance.In this paper,graphite particles of different shapes with equivalent radius of 0.1 μm were selected to study the transmittance of smoke screen based on the Monte Carlo method.The Mie scattering theory and discrete dipole approximation(DDA) method were used to calculate the single scattering extinction parameters for spherical and ellipsoidal and cylindrical particles of 1.06 μm incident light.For the transmission of incident light in the smoke,the Monte Carlo simulation model was established,the corresponding computer program was written based on MATLAB,and the calculation results of transmittance of smoke screen formed by graphite particles with different aspect ratio were given,which were compared with the corresponding smoke transmittance of equal volume spherical particles.The results show that the transmittance are related to the shapes of smoke particles,the number density of particles,the incident light angle of incidence and thickness of the smoke screen.The more deviation from the spherical shape of particles is,the smaller the corresponding transmittance is.