Particle Sizing and Velocity Measurement in Multiple Scattering Flowing Media

University Of Kansas Center For Research Inc, Lawrence KS

Investigators

Abstract

Abstract CTS-0120846 R. Dougherty, University of Kansas Center for Research Inc. Physical characterizing of the suspended particles in liquid is required for many particulate processing systems such as applications in pharmaceutical, chemical, oil, and other industries. Dynamic light scattering has been successfully used in the laboratory with limited success in industrial processes involving particulate transport. Although for single scattered light, the particle size can be accurately determined. However, multiple scattering occurring in suspension transport prevents accurate particle size or velocity measurements. To resolve this problem, previous efforts have been focused on development of correlation theories in multiple scattered problem with limited success. A novel approach is proposed here where the signals from two detectors with small but finite angular separation are cross-correlated to detect only the single scattered speckle patter. This method is proposed in combination of 'flow suppression' technique where the scattered wave vector perpendicular to the flow direction is used to avoid the disturbance due to the fluid velocity, allowing more accurate measurement of the particle size in a flowing suspension. The preliminary results for submicron particles at low velocities show some potential.