Modeling Dilute Gas-Solid Turbulent Boundary Layers Using Moment Methods

Abstract

The specific focus of the current effort is on modeling dilute particle-laden turbulent boundary layers in which the gas-phase carrier flow is populated with a second phase of small, dispersed solid particles possessing material densities much larger than that of the carrier flow. A novel approach known as the conditional quadrature method of moments (CQMOM) developed by Yuan and Fox [1], derived from the quadrature-based method of moments (QMOM) developed originally by McGraw [2], is being implemented to model the dispersed particles as an Eulerian phase. Both enabled and disabled inter-particle collision treatments are included in the model for a dispersed phase coupled to the fluid via a drag force acting on the particles. Simulations are conducted with a Reynolds number of 2800 based on the boundary layer thickness at the inlet to the domain. The full 3-D mesh contains 800×128×98 structured cells with overall dimensions in terms of the inlet boundary layer thickness of 80×6 ×4 in the streamwise, spanwise, and wall-normal directions, respectively. The gas-phase carrier flow is computed using Direct Numerical Simulation of the incompressible Navier-Stokes equations. The boundary layer develops spatially from a turbulent inflow condition and drives the particulate phase via drag and collisions. Comparisons are made against simulations performed using Lagrangian-based discrete particle simulation (DPS) of the dispersed phase and demonstrate the utility of the Eulerian moment method approach. Both instantaneous and time-averaged quantities are presented.