Droplet Breakup in High-Speed Gas Flows

Abstract

Numerical simulations are performed to study the breakup of water cylinders in the flow behind normal shocks. The computational setup is similar to previous experiments (Igra and Takayama, 2001, 2003). We examine the qualitative features of the so-called stripping breakup observed in the numerical results. Two interesting flow features are discussed: the existence of recirculation regions and an upstream jet in the wake. Various integral quantities associated with the cylinder’s deformation and acceleration are computed and compared with the experimental results, with generally good agreement. Furthermore, calculations of the velocity and acceleration of the cylinder’s center of mass provide an estimate of the unsteady drag coefficient which is approximately constant over the initial breakup period.