Effect of Obstacles Location and Flow Injection on the Mixing of Two-Gaseous Flow in a Microchannel

Document Type : Research Article

Authors

1 Faculty of Aerospace Engineering,, Semnan University, Semnan, Iran

2 Faculty of Aerospace Engineering

Abstract

In the present study, the direct simulation Monte Carlo method is utilized to investigate the effect of obstacles number, location, and also flow injection on the mixing in a channel with 16 μm length and 1 μm height. A mixing length is defined which is the length at which two species are mixed completely. Eight cases with different blockage ratios are considered to study the obstacle effect on the mixing. The blockage ratio shows the reduced flow cross-section due to the addition of obstacles. In All cases, CO2 and N2 gases enter the domain and are separated by a splitter plate that extends up to 1/3 of the channel. The blockage ratio increasing decreases mixing length by up to 10%. Whereas the mass flow rate decreased significantly. Flow injection into the channel is also studied. Four cases are considered: the first case is a simple channel without injection, the second case has cross injection, the third case has inverse injection, and flow is injected vertically through an obstacle in the fourth case. Mixing length is increased by 17% and 5% for cases 2 and 3, respectively. In case 4, the mixing length is decreased by 2% due to the obstacle.

Keywords

Main Subjects


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