论文标题
一个有效的非线性多机求解器，用于模拟稀疏气体流量
An efficient nonlinear multigrid solver for the simulation of rarefied gas cavity flow
论文作者
论文摘要
我们研究了稀疏气流的稳态有效仿真，该稳态的稳态模拟是由BGK型碰撞项的Boltzmann方程建模的。提出了一个非线性多机求解器来通过以下方法解决效率问题。首先采用了数值正规矩方法的统一框架来得出基本问题的高质量离散化。引入了快速扫描的迭代，以比单个级别网格上通常的时间整合方案更有效地解决派生的离散问题。然后建立非线性多机求解器，以显着提高收敛速率。基于OpenMP的并行化应用于实现中，以进一步加速计算。进行了两个盖子驱动的腔流量和底部加热的腔流量的数值实验，以研究所得的非线性多移民求解器的性能。所有结果表明，求解器对一阶空间离散化的效率和鲁棒性。
We study efficient simulation of steady state for rarefied gas flow, which is modeled by the Boltzmann equation with BGK-type collision term. A nonlinear multigrid solver is proposed to resolve the efficiency issue by the following approaches. The unified framework of numerical regularized moment method is first adopted to derive the high-quality discretization of the underlying problem. A fast sweeping iteration is introduced to solve the derived discrete problem more efficiently than the usual time-integration scheme on a single level grid. Taking it as the smoother, the nonlinear multigrid solver is then established to significantly improve the convergence rate. The OpenMP-based parallelization is applied in the implementation to further accelerate the computation. Numerical experiments for two lid-driven cavity flows and a bottom-heated cavity flow are carried out to investigate the performance of the resulting nonlinear multigrid solver. All results show the efficiency and robustness of the solver for both first- and second-order spatial discretization.
