小角前向散射偏振比法颗粒粒度分布反演

Inversion of particle size distribution of small angle forward scattering based on polarization ratio method

在光散射法的颗粒粒径测量方法中,传统测量模型的测量结果易受光路中颗粒杂质的影响。在Mie散射理论的基础上,将小角前向散射法与偏振比法相结合,推导了新的散射光能与粒径分布关系式,构造了传统小角前向散射法和小角前向散射偏振比法两种目标函数,并引入一种非独立模式算法——人工鱼群算法对两种方法的目标函数进行反演。仿真采用服从Johnson-SB单峰分布均匀球形颗粒,分别对两种目标函数散射光能加入5%,10%,15%的随机噪声。仿真结果显示,利用人工鱼群算法对小角前向散射偏振比法目标函数反演得到的反演精度、抗噪声能力和鲁棒性都明显优于传统小角前向散射法目标函数的反演结果。

In light scattering particle size measurement method, the results based on the traditional measurement model are easily affected by particle impurities in optical path. On the basis of Mie theory, the new relationship between scattering light energy and particle size distribution was derived by combining the small angle forward scattering method with the polarization ratio method. Two objective functions of the traditional small angle forward scattering method and the polarization ratio method of small angle forward scattering were constructed, and an independent mode algorithm, the artificial fish swarm algorithm(AFSA),was introduced to invert the objective functions. In simulations, uniform spherical particles that obey the unimodal distribution of Johnson-SB were used, and the scattering intensity values of the two target functions were added to the random noise of 5%, 10% and 15% respectively, the results demonstrate that the inversion accuracy, anti-noise performance and robustness of the polarization ratio method are significantly better than those of the traditional small angle forward scattering method.