Laser diffraction modeling based on laser and particle behaviour statistics for particle size characterization

A scattering model based on the Monte Carlo method (MCM) is developed to investigate the light scattering and extinction characteristics of non-aligned laser beams incident on a high concentration of mixed particle system. A set of measurement test systems for acquiring the scattered light energy distribution is constructed to verify the model accuracy, which yields the maximum root mean square errors (RMSE) among the MCM and the conventional model and the experimental results of 0.006 and 0.011, respectively. Subsequently, the differential evolution (DE) algorithm is introduced to deduce the particle size distribution based on the spectral content. The inversion results indicate that the MCM model can effectively correct the measurement errors caused by the non-aligned incident beams and multiple scattering effects due to high concentrations. Thus, the absolute relative errors compared with the reference values have been reduced from 33.08 % and 10.60 % for the conventional model to within 3.00 %. Additionally, three distinct sizes and mixing ratios of the mixed particle system have been successfully inverted with maximum absolute relative errors of 8.31 %, 3.14 %, and 5.41 %.