INFLUENCE OF SURFACE-ROUGHNESS OF CONDUCTING SPHERES ON THE RESPONSE OF A PHASE-DOPPLER ANEMOMETER

The influence of the surface roughness of solid conducting spheres on the response of a phase-Doppler anemometer (PDA) is described by using a ray theory model. A rough particle surface is modeled as an ensembl e of distorted spheres. First- and second-order reflection and diffrac tion are considered for far-field calculations of the PDA phase differ ence. The numerical simulations are accompanied and supported by exper imental results. Single rough Sn spheres are captured inside an electr odynamic trap and investigated with a standard phase-Doppler system.