A Cartesian Cut Cell Method for Rarefied Flow Simulations around Moving Obstacles

Guillaume Dechristé (1) , Luc Mieussens (1, 2)

1 IMB - Institut de Mathématiques de Bordeaux
2 CARDAMOM - Certified Adaptive discRete moDels for robust simulAtions of CoMplex flOws with Moving fronts

For accurate simulations of rarefied gas flows around moving obstacles, we propose a cut cell method on Cartesian grids: it allows exact conservation and accurate treatment of boundary conditions. Our approach is designed to treat Cartesian cells and various kind of cut cells by the same algorithm, with no need to identify the specific shape of each cut cell. This makes the implementation quite simple, and allows a direct extension to 3D problems. Such simulations are also made possible by using an adaptive mesh refinement technique and a hybrid parallel implementation. This is illustrated by several test cases, including a 3D unsteady simulation of the Crookes radiometer.

Mots clés: immersed boundaries; kinetic equations; rarefied gas dynamics; deterministic method; cut cell method

Domaines: Analyse numérique [math.NA]; Mécanique des fluides [physics.class-ph]

Guillaume Dechristé, Luc Mieussens. A Cartesian Cut Cell Method for Rarefied Flow Simulations around Moving Obstacles. Journal of Computational Physics, 2016, 314 (1), pp.465-488. ⟨10.1016/j.jcp.2016.03.024⟩. ⟨hal-01131756⟩