Interaction of inertial particles with eddy shocklets in high-speed turbulence*

Turbulent flows at high Mach number are characterized by the emergence of eddy shock waves, which significantly change the divergence of the velocity field and the balance of kinetic energy. In several applications, such as solid-fuel scramjets, cold spray guns, protoplanetary disks, or volcanic eruptions, these flows carry a particulate phase which additionally releases or absorbs kinetic energy. However, while the understanding and modeling of incompressible or weakly compresssible particle-laden turbulence has seen significant progress in recent years, the interaction of particles with highly-compressible turbulence is hardly understood.

 

In this contribution, detailed simulations of compressible turbulence with inertial particles are presented. Thousands of particles are fully resolved via dynamic Cartesian mesh refinement. An accurate and mass-conservative computation of the stresses at the particle surface is achieved by a cut-cell finite-volume technique. This approach is demonstrated to be robust for particles experiencing strong velocity gradients when passing through shocklets. The novel data are used to investigate the hydrodynamic forces experienced by particles in isotropic compressible turbulence, along with the particle footprint in the fluid kinetic energy balance.