Direct numerical simulation of shock-induced drop breakup with a sharp-interface-method

We present two-and three-dimensional numerical results of the shock-induced breakup of a liquid droplet in air. We apply a conservative interface interaction model for sharp-interface representation and a block-based multi-resolution scheme to adaptively refine our mesh. Numerical modeling effects, such as the flux reconstruction scheme and the use of a scale separation model, that treats non-resolved interface segments, are investigated. Similarly as a previous study (Meng, 2016), we identify two dominant mechanisms of droplet breakup at certain Mach numbers-flattening of the droplet and sheet stripping-occurring simultaneously and influencing each other in our simulations. Three-dimensional simulations show the flattening mechanism and the mushroom-like deformation of the droplet. They also explain the occurrence of a recirculation zone in the droplet wake. The two-dimensional simulations already exhibit the sheet stripping mechanism, which occurs during and after droplet flattening. Small sheets emerge from both the upstream and the downstream side of the 2D droplet, while the main sheet develops at the droplet equator.