LIGHT-SCATTERING BY HOMOGENEOUS AXISYMMETRICAL PARTICLES FOR PDA CALCULATIONS TO MEASURE BOTH AXES OF SPHEROIDAL PARTICLES

Mathematical tools are provided for the computation of the scattered f ield produced by a non-spherical particle moving through the measureme nt volume of a phase Doppler anemometer. The Doppler signal is modeled by using the rigorous extended boundary condition method and an appro ximate ray theory. The region of applicability of ray theory is discus sed. In particular, a pure refraction model is considered for large pa rticles. It is shown that under some circumstances the phase Doppler t echnique may be used for sizing of spheroidal particles.