Tracking fluid particles in subsonic, transonic and supersonic flows past a circular cylinder

Inertial and non-inertial particle-laden flows were very extensively reported in the literature for isotropic turbulence, channel flow, boundary layers, jets and wakes. By contrast, there are very few studies of circular cylinder particle-laden flow, and those only considered the incompressible, nearly two-dimensional, very-low Reynolds number range between 100 and 300, based on diameter and upstream speed. In this work, Eulerian DNS of flows past a circular cylinder for subsonic, transonic and supersonic conditions are first performed at Mach numbers of 0.2, 0.9 and 1.2 and Reynolds numbers 3,900 and 10,000. Lagrangian tracking and sampling of fluid tracer particles are then carried out in a second step. For each flow condition, 200,000 particles are released from the immediate vicinity of the cylinder surface and from a selected upstream plane. An ensemble of 8 different initial release instants are employed to increase sample size. The recorded particle velocity and position fields are used to extract statistics concerning instantaneous flow reversal and dispersion. The multiple sets of oblique and normal shock waves in the transonic and supersonic flows alter the particle behavior in an intriguing manner.