随机取向群聚椭球粒子光散射特性研究

利用离散偶极子近似方法，考虑单元粒子之间的电磁相互作用，数值计算了随机取向的不同尺度参数、不同纵横比的群聚椭球粒子的缪勒矩阵元素，给出了各个缪勒矩阵元素的角分布曲线，探讨了随机取向的群聚椭球粒子的尺度参数、纵横比、基本粒子相对位置对其缪勒矩阵元素的影响。并将随机取向群聚椭球粒子的光散射特性与单个等效球形粒子的数值结果进行了比较。结果表明，随机取向群聚椭球粒子的光散射特性与等效球形粒子的光散射特性存在很大差别，基本粒子的形状越偏离球形，这种差别就越大; 随机取向群聚椭球粒子中椭球粒子的纵横比和相对位置对整个群聚粒子的缪勒矩阵元素存在不同程度的影响，并且此影响随着粒子尺度参数的增大而变得更加显著。

Light scattering by clustered ellipsoidal particles with random orientation

Based on the discrete dipole approximation (DDA) method, the Mueller-matrix elements of clustered ellipsoidal particles with random orientation are calculated with different size parameters and aspect ratios between the elemental particles and the profiles of Mueller-matrix elements are presented. The influence of the size parameter, aspect ratio and relative position between the elemental particles on the Mueller matrices of clustered ellipsoidal particles with random orientation is discussed. Their scattering characteristics are compared with those of the equivalent spherical particles. The results indicate that there are many differences for the scattering characteristics between the clustered ellipsoidal particles and the equivalent spherical particles. The more deviation in the shape from the spherical particles, the more differences will appear. The influence of aspect ratio and relative position between the elemental particles on the Mueller matrices of clustered ellipsoidal particles with random orientation is quite large, and it varies with the size parameters of the elemental particles.