Analysis of the slip coefficient and defect velocity in the Knudsen layer of a rarefied gas using the linearized moment equations
Analysis of the slip coefficient and defect velocity in the Knudsen layer of a rarefied gas using the linearized moment equations
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DOI：
10.1103/physreve.81.016313
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发表时间：
2010-01-01
影响因子：
2.4
通讯作者：
Tang, Gui-Hua
中科院分区：
文献类型：
--
作者：
Gu, Xiao-Jun;Emerson, David R.;Tang, Gui-Hua
用线性化的R13和R26弯矩方程来研究Kramers问题。给出了缺陷速度和滑移系数的解析解，并与动力学理论的数值结果进行了比较。结果表明，线性化的R26方程能够较准确地捕捉到Knudsen层的缺陷速度和滑移系数，而线性化的R13方程低估了动力学数据。然而，在壁面，动力学模型预测的缺陷速度值比线性化的R26方程略高。一般而言，线性化的R26方程对于镜面墙和漫反射墙都表现得很好。
The linearized R13 and R26 moment equations are used to study Kramers' problem. Analytical solutions for the defect velocity and slip coefficient are derived and compared with numerical results from the kinetic theory. It is found that the linearized R26 equations can capture the Knudsen layer fairly accurately in terms of the defect velocity and slip coefficient, while the linearized R13 equations underpredict the kinetic data. At the wall, however, the kinetic models predict a slightly higher value for the defect velocity than the linearized R26 equations. In general, the linearized R26 equations perform well for both specular and diffusive walls.