Particle-laden underexpanded jets: A numerical study

We present numerical simulations of particle-laden underexpanded jets under a wide range of nozzle pressure ratios, particle sizes, and particle mass flow rates. The simulations are performed using a high-order, low dissipation Eulerian-Lagrangian framework and compared to companion experiments performed at Johns Hopkins University (Particle-laden underexpanded jets: An experimental study). The flow configuration allows for direct evaluation of gas-particle dynamics in high-speed flows exhibiting strong gas-phase compressibility. The effect of drag, mass loading on particle velocity and acceleration statistics are reported. Despite the moderately low volume fractions considered (volume loading < 0.2%), two-way coupling between the phases results in significant changes to the Mach disk location and diameter. The extent to which particles modify the Mach disk and the mechanisms responsible are reported.