| 引用本文: | 杨伟奇,杨惠.R13/R26矩方法的介观尺度壁面边界条件.[J].国防科技大学学报,2024,46(3):98-104.[点击复制] |
| YANG Weiqi,YANG Hui.Wall boundary condition for the R13/R26 moment method at mesoscopic level[J].Journal of National University of Defense Technology,2024,46(3):98-104[点击复制] |
|
| |
|
|
| 本文已被：浏览 2038次 下载 1086次 |
| R13/R26矩方法的介观尺度壁面边界条件 |
| 杨伟奇1,杨惠2 |
|
(1. 国防科技大学 空天科学学院, 湖南 长沙 410073;2. 国防科技大学 计算机学院, 湖南 长沙 410073)
|
| 摘要: |
| 宏观尺度NSF(Navier-Stokes-Fourier)、R13/R26矩方程边界条件在中、大克努森数Kn来流条件下计算精度大幅度降低,也极易发散。针对这一难题,提出R13/R26矩方程的介观尺度边界条件,在靠近壁面处重构速度分布函数,并输入介观尺度Boltzmann模型方程；基于离散速度法求解宏观参数,所得到的宏观参数作为R13/R26矩方程的壁面边界条件。仿真结果表明:基于介观尺度边界条件的R13/R26矩方法相较原边界条件计算精度最大提高59.84%,同时,所提出的边界条件将矩方法对Kn的适用范围拓展到1.0。 |
| 关键词: 稀薄气体 矩方法 非平衡流 边界条件 |
| DOI：10.11887/j.cn.202403010 |
| 投稿日期：2022-01-04 |
| 基金项目:国家自然科学基金资助项目(U1730247,12302382)；湖南省自然科学基金资助项目(2022JJ40542) |
|
| Wall boundary condition for the R13/R26 moment method at mesoscopic level |
| YANG Weiqi1, YANG Hui2 |
|
(1. College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China;2. College of Computer Science and Technology, National University of Defense Technology, Changsha 410073, China)
|
| Abstract: |
| Wall boundary conditions for the macroscopic equations, i.e. the NSF(Navier-Stokes-Fourier) equations, R13/R26 moment equations, lose their accuracy dramatically and are easy to diverge, especially in the middle and high Knudsen number regimes.To overcome these difficulties, a wall boundary condition for the R13/R26 moment method was proposed at the mesoscopic level. The velocity distribution function was reconstructed and feedback into the Boltzmann model equation in the near-wall region, and the wall boundary condition for the R13/R26 moment method was calculated on the basis of solving the Boltzmann equation with the discrete velocity method. Results indicate that:the proposed wall boundary condition is able to increase the computational accuracy up to 59.84% compared with the classical approach. Meanwhile, it is able to get the steady-state solution for the Knudsen number up to 1.0. |
| Keywords: rarefied gas moment method non-equilibrium flows boundary condition |
|
|
|
|
|
