Applications of laser Doppler anemometry in understanding food processing operations

The measurement of local fluid velocities in food processing equipment is needed for the validation of mathematical models that are used to simulate transport phenomena, and for the estimation of process parameters such as local shear rates and residence time distributions. Laser Doppler anemometry (LDA), a non-invasive technique for measuring fluid velocities, can be used to measure two- or three-dimensional flow fields in food processing equipment. In this article, the application of LDA to facilitate the understanding of fluid flow in extruders, mixers, fermenters and jet impingement ovens with the view to improving equipment performance is described.