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

Abstract

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