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

A thermally driven phase-change nonmechanical micropump has been investigated theoretically and experimentally. This micropump consisted of a microchannel and a number of uniformly-spaced heating elements along the channel. The 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-filled tube heated locally by a moving heating source. To verify the theoretical analysis, a pumping device consisting of a microchannel with twelve embedded heaters along the channel was fabricated and tested using deionized water as the working fluid. The experimental results indicate that this simple micropump can achieve a maximum pressure head of 57 mm H 2 O and a maximum volumetric flow rate of 300 µl 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 found that the theoretical model is in reasonable agreement with the experimental data.