Characterization of a Sub-Atmospheric Pressure-Inducing Micropump Based on Flow Rate and Gauge Pressure Measurements

The pumping mechanism in multi-inlet microfluidic channels usually requires multiple micropumps to be separately attached to each inlet. Unfortunately, this may create fluid leakage resulting from a considerably high internal pressure. To address this, a passive sub-atmospheric pressure-inducing micropump is proposed and its performance is characterized as a function of the flow rate and the gauge pressure. With this pump, a sufficiently high flow rate is generated, comparable to some active-piezoelectric micropumps. The gauge pressure is exponentially descending with time and can be crudely classified into three regions of high, moderate, and slow pressure-release times. Overall, the stabilized pressure is identified within 70 s < t <= 300 s for slow rate mixing while rapid mixing is applicable at t <= 70 s.