Kinetic-theoretic studies of the effect of sharp edges of the boundary in low-pressure gases

低压气体边界锐边效应的动力学理论研究

基本信息

批准号：
10650171
负责人：
AOKI Kazuo
金额：
$ 1.92万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650171/
关键词：
low-pressure gases Boltzmann equation velocity distribution function propagation of singularities Knudsen number kinetic theory of gases rarefied gas dynamics mean free path 端的特異性熱ほふく流

项目摘要

1. Study of a rarefied gas flow induced around edges of a uniformly cooled or heated plate :In our previous paper, we showed, by means of a numerical analysis using the direct simulation Monte Carlo method, that a fairly strong gas flow is induced around the edges of a uniformly cooled or heated plate placed in a rarefied gas. In the present study, in order to obtain the result with higher reliability, we investigated the flow by an accurate finite-difference analysis of a kinetic equation. As a result, the behavior of the gas was clarified comprehensively. In particular, it was confirmed that the flow has a stronger effect than the thermal creep flow and the flow induced by the thermal stress in the near continuum case.2. Study of a rarefied gas flow caused by a discontinuous wall temperature :We have investigated a rarefied gas flow induced in a container when the temperature of the wall of the container has a discontinuous distribution. The flow was obtained accurately for a wide ra … More nge of the degree of gas rarefaction by applying the finite-difference method developed in 1. We showed that, as the continuum limit is approached, though the region with an appreciable flow shrinks to the discontinuity line of the wall temperature, the maximum speed of the flow tends to approach a finite value. In addition, we have clarified the propagation of singularities, caused by the singularities in the boundary data, mathematically on the basis of a simple transport equation that possesses the feature of the equations in kinetic theory of gases.3. Studies of some other fundamental problems :Paying attention to another aspect of a well-known flow induced by a temperature field (thermal transpiration), we studied the control of the flow in a pipe (e. g., causing a one-way flow) by devising the temperature distribution as well as the configuration of the pipe. We have also investigated the fundamental features of the continuum limit for gas mixtures, the understanding of which facilitates the extension of the analyses of 1 and 2 to the case of the mixtures. Less

1。研究均匀冷却或加热板的边缘稀疏的研究：在我们的上一篇论文中，通过使用直接模拟蒙特卡洛方法显示SIS，即在均匀冷却或加热放置的边缘周围诱导相当强的气流在本研究中，稀有气体通过对气体的行为进行了精确的差异分析，以全面阐明该流量。在接近连续的情况下。2。通过应用1在1中开发的有限差异方法的气体罕见程度。我们表明，连续限制已接近，尽管该区域具有明显的溜冰场，距离壁温度的最大速度是最大的速度流动倾向于接近有限的价值，此外，奇异性的传播，边界数据中的奇异性是气体动力学理论中方程的特征。3通过设计温度分布以及管道的配置，由管道中的温度场引起的众所周知的流动（例如，导致一周的流动）。混合剂的情况少。