On the light-scatter technique for the study of turbulence and mixing

Abstract

The light-scatter technique facilitates study of the concentration field when one of the streams entering a mixing region is marked with colloidal particles. The present paper provides basic information for the effective application of the technique. The system response is analysed theoretically. The problems of noise and spatial resolution are examined and experimental data are presented from which the response parameters are evaluated numerically. The capabilities of the technique for characterizing turbulent concentration fluctuations are described. The technique is excellent in the convection region of the turbulence spectrum but fails where molecular diffusion is important.