Modelling and test of a thermally-driven phase-change nonmechanical micropump

A thermally driven phase-change nonmechanical micropump has been investigat ed theoretically and experimentally. This micropump consisted of a microcha nnel and a number of uniformly-spaced heating elements along the channel. T he pumping of fluids in such a pump was realized by using the actuation of a moving vapour slug (bubble) generated by suitably phased heating elements . The pumping mechanism was studied theoretically by considering a liquid-f illed tube heated locally by a moving heating source. To verify the theoret ical analysis, a pumping device consisting of a microchannel with twelve em bedded heaters along the channel was fabricated and tested using deionized water as the working fluid. The experimental results indicate that this sim ple micropump can achieve a maximum pressure head of 57 mm H2O and a maximu m volumetric flow rate of 300 mul min(-1) when it is operated for a heating power ranging from 8.0 to 12.0 W and a heating time of about 3 s. It is fo und that the theoretical model is in reasonable agreement with the experime ntal data.