A simple model is proposed for the phase-space distribution of dispersed, high-inertia particles in a turbulent boundary layer. This model includes a boundary condition describing inelastic particle–wall collisions. Two models for the normal coefficient of restitution are considered. The simpler model treats this coefficient as a constant, and this is shown to lead to a singular distribution of particle velocities at the boundary. A numerical scheme for treating this model is presented, and results from this are compared with those obtained from particle random-walk simulations. An asymptotic analysis is given for this singular model; the asymptotic behavior of the phase-space distribution shows that the one-dimensional steady state distribution exists only for relatively high values of the coefficient of restitution, ε>0.5. The more detailed model for the coefficient of restitution treats this coefficient as a function of the normal impact velocity. Numerical results from this model are also given and compared with those obtained by simulation. For both models the particle number density and particle fluctuation energy at the wall, required to formulate boundary conditions for the “macroscopic” two-fluid models, are calculated as functions of model parameters. The results also illustrate the phenomenon of particle segregation towards the wall in turbulent gas-particulate suspensions, i.e., the formation of the near-wall dense layer of particles; the thickness of this layer is also determined as a function of model parameters.

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