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A multi-chamber piezoelectric pump based on pumping unit with double circular piezoelectric unimorph actuators

For improving flow rate of multi-chamber piezoelectric pump with active valves, principle and structure of multi-chamber piezoelectric pump based on pumping unit with double circular piezoelectric unimorph actuators (CPUAs) are proposed. Double CPUAs are coaxially and symmetrically arranged on top and bottom of pump chamber and work in same frequency and phase at same time to provide driving force for pump. Two active piezoelectric valves with annular boundary are designed on left and right of pumping unit to ensure the multi-chamber piezoelectric pump bidirectionally pump fluid with high control accuracy and stop characteristics. Process compatible with printed circuit board (PCB) process is used to manufacture pump to ensure low cost. Flow rate model is established to numerically simulate flow characteristics of the pump. Pump is also experimentally tested and analyzed. Results show that proposed principle and structure can effectively improve flow rate and out pressure of multi-chamber piezoelectric pump with high control accuracy and stop characteristics of flow. Moreover, flow rate model can accurately describe its flow characteristics, which will be beneficial to design and optimize multi-chamber piezoelectric pumps with active valves. Proposed principle and structure of multi-chamber piezoelectric pumps with active valves have potential applications in complex microfluidic systems such as biochemical analysis, drug delivery and chip cooling.