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

In the present study, direct simulation Monte Carlo method is utilized to investigate the effect of obstacles number, location and also injection of a flow on the mixing of flow 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 ratio are considered to study obstacle effect on the mixing. Blockage ratio shows the reduced flow cross section due to addition of obstacles. In All cases CO2 and N2 gases enters the domain and separated by a splitter plate which extends up to 1/3 of channel. Blockage ratio increasing decreases mixing length up to 10%. Whereas mass flow rate decrease significantly. Flow injection into channel is also studied. Four cases are considered: the first case is simple channel without injection, second case has cross injection, third case has inverse injection, and flow is injected vertically through an obstacle in forth case. Mixing length is increased 17% and 5% for case 2 and case 3, respectively. In case 4, mixing length is decreased 2% due to the obstacle. In case 2 and 3,