对于角点处的反弹格式处理

journeyhope

请问对于角点处反弹格式需不需要特殊处理？
能否推荐篇相关文献呢？
谢谢！

hawlin

每个角点都需要另外处理，这个对于程序稳定性很重要，可以参考文献Zou, Q. and X. He (1997). "On pressure and velocity boundary conditions for the lattice Boltzmann BGK model." Physics of Fluids 9(6): 1591.

luo@odu.edu

Sharp Corners are singularities, thus finite-difference (FD) methods are not good to deal with them. The LBE is in fact a FD method thus it has difficulty to handle sharp corners. Having said that, MRT-LBE with bounce-back BCs in general works well to deal with corners.

When we simulate the 2D cavity flow, which has 2 top corner singularities, the MRT/TRT LBE works well.

Reference
L.-S. Luo, W. Liao, X. Chen, Y. Peng, and W. Zhang.
Numerics of the lattice Boltzmann method: Effects of collision models on the lattice Boltzmann simulations.
Physical Review E 83(5):056710 (May 2011).

onesupeng

没有一种方法能够绝对处理奇性，只能增加一定的网格，让奇性处理引起的误差不致对周围大片区域产生显著影响，例如顶盖流动运动板与两侧壁面的角点。

wghuang

请教 Cavity flow角点的处理方法?
是在顶盖之上再增加数层流体格点吗?
那么速度边条件该施加在哪里?

luo@odu.edu

Grid refinement can exacerbate numerical instability due to singularities. Tricks favored by some applied mathematicians are: (1) singularity removal technique and (2) "regularization".

luo@odu.edu

Learn how to use MRT+LBE and bounce-back BCs. For the cavity flow, I have not seen better way than that (within the context of LBM).