A study of flows in tangentially crossing micro-channels

In the present study, flow fields in the three-dimensional, tangentially crossing micro-channels were studied. The effect of the relevant geometrical parameters such as the aspect ratio, contact surface area, surface to volume factor, flow rate and cross angle on the flow turning was reported. When the geometries and the flow conditions of the two crossing channels were the same, the fraction of turning flow was found to be dependent on the aspect ratio of the channel as reported previously in the literature. However, if the configuration and flow conditions of the two channels were different, the results need to be clarified. A parameter of non-dimensionalized surface to volume ratio was devised to characterize the flow turning. And the parameter was tested against its validity using numerical simulation and the available experimental data. The experiments on the crossing angle were conducted to show that larger angle in general yielded higher turning flow ratio. The results are expected to be useful in the passive control of flow in micro-fluidic devices among others.