Monte Carlo calculation of backscattered light intensity by suspension: comparison with experimental data.

An optical device for measuring high particle concentrations is presented. The sensor consists of two optical fibers used for the emission and reception of the light scattered by particles in suspension. To describe the light path in this medium, we developed a Monte Carlo calculation including a mean free path, a phase function for particle scattering, and an absorption rate. A similarity law links concentration variations to a homothetic space transformation. A comparison between our calculation and experimental data is given for well-stirred, dense suspensions of silica particles with different sizes. A good fit is found when the model parameters (mean free path and phase function) are chosen according to the data given by a particle sizer.