摘要
采用格子Boltzmann方法(LBM)对过渡区内的微尺度气体流动进行了模拟研究。在已有滑移区微流动LBM模型中引入Knudsen层速度修正,选取合适的修正函数表达式并依据动理论确定了可调参数的合理取值。在边界条件的处理格式上,采用了适合过渡区模拟的高阶滑移边界的替代格式来捕捉过渡区微流动的滑移速度,避免了直接求解高阶速度导数项的数值困难。通过对两类不同的微流动进行模拟的结果表明:与数值解吻合得较好,尤其是对Kn>0.5微流动滑移速度的预测,与已有LBM的模拟结果相比有明显的提高。
In this paper, gas micro-flows in transition regime have been investigated by lattice Boltzmann method （LBM）. On the basis of existing LBM models for micro-flows simulation, the velocity correction function for Knudsen layer was introduced into the model. And the appropriate expression of velocity correction was chosen with the suitable parameter according to the kinetic theory. In the treatment of boundary condition, to avoid the difficulties posed by computing the higher-order derivatives of the velocity, we took a substitute approach of higher-order slip scheme to capture the slip velocity in transitional regime. The present results of two types of micro-flows agree well with the numerical solutions, and are evidently better than those with the former LBM simulations, especially in the case of Kn 〉 0.5.
出处
《力学学报》
EI
CSCD
北大核心
2009年第6期828-834,共7页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家重点基础研究发展计划(2006CB705800)
中国地质大学优秀青年教师资助计划(CUGQNL0904)
煤燃烧国家重点实验室开放基金(FSKLCC0815)资助项目~~
