Numerical study of an original device to generate compressible flow in microchannels

摘要

This study is devoted to the design of an experimental device to generate shock waves in a micropipe. Indeed, the recent advances in the microfluidics of gas lead the scientific community to the question of scaling law in supersonic regime. Thus, in this paper, we simulate the flow induced by the opening of a small solenoid valve to know if it is able to generate a minishock wave. This shock wave moving in an intermediate pipe could be transmitted into a micro one. In this work, we focus on the flow in the intermediate pipe and on the properties of the transmitted wave into the microchannel. Three geometry of convergent between intermediate and micropipe are investigated. We have compared the results of our simulation to the classical analytical models dealing with shock tubes. After presenting the geometries of the study case, we give the characteristics of our numerical approach, and then we describe our main results. In a last section, the flow generated by the valve used in free jet regime is described. (C) 2008 American Institute of Physics.