Abstract: A valveless piezoelectric pump with Y-elements is assembled by installing two inverted Y-shape tees to the chamber, which is composed inlet, outlet, piezoelectric vibrator, chamber and other parts. This pump has no chemical and electromagnetic pollution sources, nor periodic valves opening or closing. It also characters potentiality to be miniaturized and integrated. This pump facilitates to transfusing living cells and macromolecular compound because only lower-intensity eddy field occurs when pump fluid flows through the Y-elements. Firstly, the structure of the new valveless piezoelectric pump with Y-elements is presented. Then, pressure distribution and velocity vector distribution in the Y-elements are simulated by means of finite volume method, which proves when fluid flows through Y-elements the eddy field is far lower than that in diffuser/nozzle elements. Simulations also show that the fluctuations of the pressure and velocity in Y-elements are much lower. Thirdly, the equation of volume change is built through analyzing vibration of the piezoelectric vibrator. And the theoretical relationship between the flow rate and the frequencies of piezoelectric vibrator is established. Finally, through the flow test this device with Y-elements is proved to have the characteristics of pump, thus proving the correctness of the theoretical model presented above.

Key words: Eddy field, Flux, Piezoelectric pump, Y-shape tubes