Performance analysis of a device for gas transport and compression by making use of porous media on the basis of kinetic theory

在气体分子的平均自由程与系统特征长度相比不可忽略的小系统中，气体中的温度场诱导稳定的流动。在这项研究中，研究了由具有非常小的孔洞的多孔介质在热诱导流驱动下组成的泵送装置的性能。更准确地说，利用建立在动力学理论基础上的扩散模型，研究了由许多方形圆柱体阵列组成的装置中的稀薄气体流动。例如，当每个阵列中加热和非加热侧的温度比为1.5时，当根据相邻圆柱体中心之间的距离计算的克努森数为6时，该装置可以通过使用100个阵列来维持50的压比。

In a small system where the mean free path of the gas molecules is not negligibly small compared to the system characteristic length, a steady flow is induced by the temperature field in a gas. In this study, the performance of a pumping device composed of porous media with very small pores driven by a thermally induced flow is examined. More precisely, a rarefied gas flow in a device composed of many square arrays of circular cylinders is investigated by making use of a diffusion model derived on the basis of kinetic theory. It is shown, for example, that the device can maintain the pressure ratio of 50 by using 100 arrays, when the temperature ratio between heated and unheated sides in each array is 1.5 and when the Knudsen number based on the distance between the centers of adjacent cylinders is 6.