Analysis on flow field of the valveless piezoelectric system with a rotating unsymmetrical slopes element

摘要

A new valveless piezoelectric pump, which integrates mixer and pump, is proposed, based on the theory of the piezoelectric pump with the Unsymmetrical Slopes Element(USE). It is designed not only two inlets and one outlet, but a Rotatable Unsymmetrical Slopes Element(RUSE). When the pump works, two fluids flow into the inlet channels, respectively. The RUSE can be rotated to adjust the flow resistances of the two inlet channels and varies their flows. It can realize the ratio control of the two flows. The fluids form a net flow due to the USE principle, while they are mixed into a homogeneous solution due to strong turbulence flow field and complex vortexes generated by RUSE in the chamber. And then the solution is exhaust out of the outlet. All of these processes realize the integration of mixing and pumping functions. Firstly, theoretical analysis on this pump is performed. Meanwhile, the flow field in the chamber is calculated and simulated. And then, the relationship between the flow of the pump and the rotating angle of the RUSE is established and analyzed. Finally, experiment on this pump is carried on. It shows that the empirical data and the theoretical data share the same tend. On condition of 20° RUSE, the maximum error between the theoretical flow and the empirical flow is 11.14%, and the maximum error between the theoretical flow ratio of the two inlets and the experimental one is 2.5%. All of these verify the theoretical analysis.