Multiple-beam laser velocimeter: analysis and applications.

In the multiple-beam laser velocimeter a large number of beams intersect to form sharp intense spots well separated by dark areas. The correlation function for particles moving through such an intensity distribution is calculated from first principles and verified experimentally. Interpretations of systems with a distribution of particle velocities can be made with less ambiguity using the multiple-beam laser velocimeter rather than the conventional two-beam model. The technique is demonstrated by measuring the velocity distribution of particles in a fast fluidized bed.