Pumping Mechanism of Thermally Driven Phase Transition Micropump

The theoretical analysis and the experimental investigation for the thermally driven phase transition micropump are performed. Firstly, single-phase flow driven by a moving heat source is simulated to reveal the pumping effect. Then, a simplified model for the thermally driven phase transition micropump is established in a coordinate system moving with the heater. The pumping mechanism and characteristics are analytically and numerically analyzed. The results indicate that the thermally driven flow comes from the asymmetrical fluid property distributions, and an optimal distribution of phases is essential to get the best pumping effect. Experimental results show that an optimum heating and cooling condition is necessary for the maximum flow rate, which proves the rationality of the analysis.