ABSTRACT
Multiphase flow refers to the motion of a mixture of solid particulates in liquids or gases, liquid droplets in gases, gas bubbles in liquids, or solid particulates and gas bubbles mixed in liquids. Optical methods of flow visualization are most appropriate for multiphase flow. Images of the flow field can be processed to yield whole-field velocity measurements. The local velocity is determined by dividing the change in the locations of the tracer images at two or more times by the time interval. This method is referred to as pulsed-light velocimetry (PLV). Two kinds of tracers have been used: particles and molecules. A sheet of light that is pulsed illuminates tracer particles in the fluid. In contrast, PTV has the concentration of scattering so small that images are sparse in the image plane and individual images can be easily identified. Image analysis is performed on the recorded picture.
