Size distribution of particle systems analyzed with organic photodetectors

TL;DR

This paper explores the use of organic photodetectors for optical particle sizing in suspensions, developing a Monte-Carlo model to optimize system performance and analyze particle size distributions in various media.

Contribution

It introduces a novel optical particle sizing method using organic photodetectors and a comprehensive Monte-Carlo model to evaluate system performance in different scattering regimes.

Findings

Effective particle size analysis in dilute media using scattering diagram inversion

Backscattering spotlight analysis for dense media characterization

Monte-Carlo model accurately predicts system behavior under various parameters

Abstract

As part of a consortium between academic and industry, this PhD work investigates the interest and capabilities of organic photo-sensors (OPS) for the optical characterization of suspensions and two-phase flows. The principle of new optical particle sizing instruments is proposed to characterize particle systems confined in a cylinder glass (standard configuration for Process Analytical Technologies). To evaluate and optimize the performance of these systems, a Monte-Carlo model has been specifically developed. This model accounts for the numerous parameters of the system: laser beam profile, mirrors, lenses, sample cell, particle medium properties (concentration, mean & standard deviation, refractive indices), OPS shape and positions, etc. Light scattering by particles is treated either by using Lorenz-Mie theory, Debye, or a hybrid model (that takes into account the geometrical and physical contributions). For diluted media (single scattering), particle size analysis is based on the inversion of scattering diagrams obtained over a wide angular range or near optical singularities (rainbow, critical scattering, diffraction). For dense media (multiple scattering), the solutions foreseen are based on the analysis of the backscattering spotlight characteristics.