hybridDCFoam: A coupled DSMC/Navier–Stokes–Fourier solver for steady-state multiscale rarefied gas flows
Nikos Vasileiadis, Craig White
Abstract
This paper presents the development and validation of hybridDCFoam, a coupled DSMC/Navier–Stokes–Fourier solver, for simulating steady-state multiscale rarefied gas flows. The developed solver is based on the domain decomposition method, while the state-based information exchange approach is implemented between the particle and continuum solvers. The solver is developed within the OpenFOAM framework and couples the dsmcFoam+ and rhoCentralFoam solvers in order to handle the particle and continuum flow regions. hybridDCFoam can tackle arbitrary 3D geometries and supports parallel simulations using the MPI domain decomposition available in OpenFOAM. The developed solver is validated for flow over a flat plate, flow past a cylinder, pressure-driven flow through a slit, and expansion through a conical nozzle. The presented benchmarks yield an excellent agreement between hybrid and pure DSMC simulations. Moreover, hybridDCFoam is able to accurately recover both numerical and experimental results reported in the literature. Notably, hybridDCFoam achieves significant computational gains compared to pure dsmcFoam+ simulations, rendering it well-suited for addressing multiscale rarefied gas flows of engineering importance.