The dependence of transport coefficient on spatial dimensions and grid shape in the direct simulation Monte Carlo based on Green–Kubo relation.

Since the essence of the direct simulation Monte Carlo program is to decouple the motion and collision of molecules, this will cause errors of gas transport properties or the collision separation error (CSE). Based on the Green–Kubo relation, this paper studies the dependence of the CSE on the spatial dimension and grid shape, especially the anisotropy of gas transport properties for various collision schemes in multi-dimensional spaces. The results show that the CSEs caused by the traditional no time counter and the simplified Bernoulli-Trials collision schemes in different dimensional spaces are consistent, and they are isotropic for some grid shapes, while the CSE caused by the nearest neighbor method depends on the spatial dimension, and it is anisotropic. These results are verified by simulation of one-dimensional Fourier flow. [ABSTRACT FROM AUTHOR]