Dispersion of a cloud of particles by a moving shock: Effects of the shape, angle of rotation, and aspect ratio

Abstract

This paper discusses the particle-laden flow development from a cloud of particles in an accelerated flow behind a normal moving shock. The effects of the aspect ratio of a rectangular and ellipsoidal cloud and the cloud’s angle of attack with respect to the carrier flow are studied. Computations are performed with an in-house high-order weighted essentially non-oscillatory (WENO-Z) finite-difference scheme-based Eulerian-Lagrangian solver that solves the conservation equations in the Eulerian frame, while particles are traced in the Lagrangian frame. Streamlined elliptically shaped clouds exhibit a lower dispersion than blunt rectangular clouds. The averaged and root-mean-square locations of the particle coordinates in the cloud show that the cloud’s streamwise convection velocity increases with decreasing aspect ratio. With increasing rotation angle, the cross-stream dispersion increases if the aspect ratio is larger than unity. The particle-laden flow development of an initially moderately rotated rectangle is qualitatively and quantitatively comparable to the dispersion of an initially triangular cloud.