Experimental Technique for the Measurement of Velocity and Droplet Lag Distance in a Shock Accelerated Multiphase System

A shock tube study has been conducted to investigate hydrodynamic instabilities that arise from the impulsive acceleration of a heterogeneously seeded multiphase field. In the experiment, a cylindrical interface comprised of micron sized acetone droplets seeded in nitrogen was created in a test section and accelerated by a planar shock wave. Nitrogen saturated with acetone vapor was mixed into the interface as a tracer and to prevent early evaporation of droplets. The development of both the dispersed and carrier phases was captured through a series of Planar Laser Mie Scattering (PLMS) and Planar Laser Induced Fluorescence (PLIF) images respectively. Lag effects between the phases were visualized and quantified. Velocity fields from images were constructed, and the results were compared to simulations for validation. This study has applications in many scientific and engineering systems, but has particular relevance to systems that involve high speed or shock induced multiphase combustion.