An immersed boundary method-discrete unified gas kinetic scheme simulation of particle-laden turbulent channel flow on a nonuniform orthogonal mesh

Particle-resolved simulations of turbulent particle-laden flows provide a powerful research tool to explore detailed flow physics at all scales. However, efficient particle-resolved simulations for wall-bounded turbulent particle-laden flows remain a challenging task. In this article, we develop a simulation approach for a turbulent channel flow laden with finite-size particles on a nonuniform mesh by combining the discrete unified gas kinetic scheme (DUGKS) and the immersed boundary method (IBM). The standard discrete delta function was modified according to reproducible kernel particle method to take into account mesh non-uniformity and correctly conserve force moments. Simulation results based on uniform and nonuniform meshes are compared to validate and examine the accuracy of the nonuniform mesh DUGKS-IBM. Finally, the computational performance of the nonuniform mesh DUGKS-IBM is discussed.