Development of a vacuum pump without a moving part with the aid of thermal transpiration flow of a rarefied gas

借助稀薄气体的热蒸腾流开发无运动部件的真空泵

• 批准号: 09555064
• 负责人: SONE Yoshio
• 金额: $ 5.18万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555064/
• 关键词: vacuum pump; thermal transpiration flow; Poiseulle flow; rarefied gas; Boltzmann equation; molecular gas dynamics; evaporation and condensation; vacuum technology

The subject that we proposed is studied in the following two directions.1. Flows induced in a rarefied gas by its temperature fieldThe comprehensive study of flows induced by temperature fields is made in order to find the possibility of constructing a pump without any moving part with the aid of the flow.(1) It is experimentally observed for the first time that a flow is induced around the edge of a uniformly heated plate.(2) Flows induced between two coaxial elliptic cylinders with different temperatures are studied numerically on the basis of kinetic theory for the whole range of the Knudsen number. The configuration of the flow is found to be considerably affected by the global geometry of the system except in the case of small Knudsen numbers.(3) One-way flows induced in a circular pipe with a periodic temperature distribution and with ditches periodically dug are studied numerically in details. The pumping effect is found to be several times larger than that of the channel flows … More studied previously by Sone et al.(4) It is experimentally observed that a one-way flow is induced in a pipe without average pressure and temperature gradients, as in item (3). The experiment shows that the shape of the pipe is essential to inducing a one-way flow.(5) The results obtained, combined with those of our previous research, are formed into a systematic survey of flows induced by temperature fields.These studies show that a pumping system without a moving part is not difficult to be realized with the aid of the thermal transpiration.2. Flows with evaporation or condensation in relation to a cryo-pumping system(1) Weak evaporation from or condensation onto a spherical condensed phase are studied analytically and numerically on the basis of kinetic theory, and the detailed behavior of the flow is clarified for the whole range of the Knudsen number. Further, Onsager's relation is shown to hold for arbitrary Knudsen numbers.(2) Transonic condensing flows onto a plane condensed phase are studied analytically. The analytic structure of the solution, especially, the discontinuous change of the range of existence of a solution across the sonic point is clarified.(3) Cylindrical Couette flows between two axial circular cylindrical condensed phases are studied in details. New type of bifurcation is found to exist, and the range of the parameters where the bifurcation takes place and its physical mechanism etc. are clarified. Less

我们提出的课题从以下两个方向进行研究。温度场在稀薄气体中的诱导流动本文对温度场诱导的流动进行了全面的研究，以期找到利用该流动构造无任何运动部件的泵的可能性。(1)首次实验观察到在均匀加热板的边缘附近产生流动。(2)基于Knudsen数全范围的动力学理论，对两个不同温度的同轴椭圆柱之间的诱导流动进行了数值研究。除了较小的Knudsen数外，系统的整体几何形状对流动形态有很大的影响。(3)数值研究了周期性温度分布的圆形管道和周期性开挖的沟渠中的单向流动。发现泵浦效应比沟道流…的泵浦效应大好几倍之前由Sone等人进行了更多的研究。(4)实验观察到，在没有平均压力和温度梯度的情况下，在管道中诱导单向流动，如在第(3)项中。实验表明，管道的形状对诱导单向流动是必不可少的。(5)结合我们以前的研究结果，对温度场诱导的流动进行了系统的考察，这些研究表明，在没有移动部件的情况下，借助热蒸腾实现抽水系统并不困难。以动力学理论为基础，对有蒸发或凝结的流动进行了分析和数值研究：(1)从球形凝聚相弱蒸发或凝结到球形凝聚相上的流动，阐明了在整个克努森数范围内流动的详细行为。此外，对于任意的克努森数，Onsager关系也成立。(2)对平面凝聚相跨音速凝聚流动进行了解析研究。阐明了解的解析结构，特别是解的存在范围在音速点上的不连续变化。(3)详细研究了两轴向柱状凝聚相之间的柱状Couette流动。发现了新型分叉的存在，并阐明了发生分叉的参数范围及其物理机制等。较少

项目成果

Yoshio Sone: "Analytical study of transonic flows of a gas condensing onto its plane condensed phase on the basis of kinetic theory" European Journal of Mechanics,B/Fluids. 17・3. 277-306 (1998)

Yoshio Sone：“基于动力学理论的气体凝结到其平面凝聚相的跨音速流动的分析”《欧洲力学杂志》，B/Fluids 17・3（1998）。

Y.Sone: ""Flows induced by temperature fields in a rarefied gas and their ghost effect on the behavior of a gas in the continuum limit"" Annual Review of Fluid Mechanics. (to be published).

Y.Sone：“稀薄气体中温度场引起的流动及其对连续介质极限中气体行为的幽灵效应”《流体力学年度评论》。

Yoshio Sone: "Demonstration of a rarefied gas flow induced near the edge of a uniformly heated plate" Phisics of Fluids. 9. 3530-3534 (1997)

Yoshio Sone：“演示在均匀加热板边缘附近诱导的稀薄气流”流体物理学。

Sigeru Takata: "Evaporation from or condensation onto a sphere : Numerical analysis of the Boltzmann equation for hard-sphere molecules" Computers and Mathematics with Applications. 35. 193-214 (1998)

Sigeru Takata：“从球体蒸发或凝结到球体：硬球分子玻尔兹曼方程的数值分析”计算机和数学及其应用。

Yoshio Sone: "Analytical study of transonic flows of a gas condensing onto its plane condensed phase on the basis of kinetic theory" European Journal of Mechanics, B/Fluids. 17. 277-306 (1998)

Yoshio Sone：“基于动力学理论对气体凝结到其平面凝相上的跨音速流动的分析研究”《欧洲力学杂志》，B/流体。