Abstract
This paper presents a micro air pump based on the synthetic jet to supply reactant at the cathode side for micro fuel cells. The synthetic jet is a zero mass flux device that converts electrical energy into the momentum. The synthetic jet actuation is usually generated by a traditional PZT-driven actuator, which consists of a small cylindrical cavity, orifices and PZT diaphragms. Therefore, it is very important that the design parameters are optimized because of the simple configuration. To design the synthetic jet micro air pump, a numerical analysis has been conducted for flow characteristics with respect to various geometries. From results of numerical analysis, the micro air pump has been fabricated by the PDMS replication process. The most important design factors of the micro air pump in micro fuel cells are the small size and low power consumption. To satisfy the design targets, we used SP4423 micro chip that is high voltage output DC-AC converter to control the PZT. The SP4423 micro chips can operate from $2.2{\sim}6V$ power supply(or battery) and is capable of supplying up to 200V signals. So it is possible to make small size controller and low power consumption under 0.1W. The size of micro air pump was $16{\times}13{\times}3mm^3$ and the performance test was conducted. With a voltage of 3V at 800Hz, the air pump's flow rate was 2.4cc/min and its power consumption was only 0.15W.
