摘要：为了深入了解多分散体系下动态光散射信号特性及相应反演算法的改进优化,基于溶液中三维布朗运动和相干光学理论,提出一种动态光散射数值模拟方法,并推导多分散体系中总散射光强及归一化自相关函数的数值表达式;分别模拟单分散颗粒体系及含2种不同粒径组分的双分散颗粒体系的动态光散射光强信号,同时计算相应的归一化自相关函数曲线;研究颗粒数与总采样时间对相关曲线的影响。结果表明,模拟光强信号的自相关函数曲线与实验测得及理论曲线能很好地吻合,证明了该模拟方法的正确性。

关键词：动态光散射；多分散体系；布朗运动；自相关函数；信号模拟

Abstract： To optimize the scattering equipment and inversion algorithm， especially for polydisperse particle systems， based on the theory of three-dimensional Brownian motion and coherent optics， a numerical method of simulating dynamic light scattering signals was developed. The expression of the total intensity of scattered light and normalized autocorrelation function in polydisperse particle systems were derived. The dynamic light scattering intensity from monodisperse particle systems and polydisperse particle systems were simulated. The effect of particle numbers and total sample time on correlation function curves was studied. The results show that the calculated autocorrelation functions of the simulated intensity signals agree well with those of theories， which demonstrates the effectiveness of the numerical method. 

Keywords: dynamic light scattering； polydisperse system； Brownian motion； autocorrelation function； signal simulation