Numerical and Experimental Analysis of Laminar Flows through a T-junction Micromixer

In this work, a numerical and experimental analysis have been carried out in order to analyze the behaviour of laminar water flows through a confluent micro T-junction. The micro T-junction is made as intersection of two glass microchannels with a trapezoidal cross-section with a width of 300 μm and a height of 265 μm with apex angles of 88°. The mixing of the flows is obtained by the injection of water flow into two perpendicular branches of the T-junction. The streams mix themselves in the correspondence of the junction and flow to the outlet branch which is parallel to the main inlet. A μPIV apparatus has been used for the experimental determination of the velocity profiles within the micromixer and the experimental results have been compared with the numerical results carried out by using a commercial CFD code (Comsol Multiphysics™). The results presented in this work demonstrate that it is possible to obtain a very accurate reconstruction of the velocity field within the T-junction by using the μPIV technique with a rRMS error between 2.9% and 5.4%.