Theoretical and Experimental Analysis of Active Valve Pumping for High Flow Rate Applications

A new valve-only micropump structure for gas applications is proposed consisting of electrostatically actuated checkerboard microvalves with dual cavities. The valve-only multistage peristaltic design minimizes complexity and footprint of the device, which allows operation at high frequency, better sealing and efficient operation. A previously developed reduced order model is used to design and analyze the performance of the system. In this paper the effect of the cavity height on the performance and stability of this system is explored. The fabricated micropump produced a flow rate of 140 μl/min at 1 kHz operation despite the cavity and membrane resonance being > 20 kHz. Four micropumps having cavity heights of 45, 60, 90 and 120 μm are explored in the modeling efforts using sinusoidal waveforms. It is found that an optimum cavity height exists which maximizes pump performance. Decreasing the cavity height below this value increases acoustic pressure damping, which in turn increases instability of the system.