Research On Valveless Piezoelectric Pump With Y-shape Tubes

This subject was granted by the National Natural Science Foundation Project—Research on Fluid Dynamics and Application of Valveless Piezoelectric Pump with Y-shape tubes for Transporting Cells and Macromolecule (Project no. 50575007).Piezoelectric pump is simple in its structure and has many advantages different from traditional pumps, so it has wide applications in the fields of aeronautics and astronautics, robot, car, medical apparatus, creature genetic engineering and micro-machine, etc. However, many researches on valveless piezoelectric pump, taking medical treatment, sanitation and health care as their research backgrounds, take no account of the effects of vortex and onflow existing in the chamber and tubes of the pump. This thesis analyzed the drawbacks of other types of valveless piezoelectric pump in their structures, and then proposed a novel type of valveless piezoelectric pump—valveless piezoelectric pump with Y-shape tubes(VPPYT).The main research achievements and work are summarized as follows:In the aspect of the vibration analysis on piezoelectric actuator, formulas for the calculation of inherent frequency & maximum displacement of the piezoelectric actuator are deduced. Next, FEM model for the actuator was established to verify the correctness of theoretical analysis. Finally, the effects of geometrical parameters (diameter ratio, thickness ratio) and base material parameters on the actuator performance have been investigated, which provides a good reference for optimizing the design and manufacture of other types of piezoelectric pump.In the aspect of the fluid analysis on VPPYT, firstly the formula to calculate the flow rate is deduced. And then based on finite volume method, fluid calculation and analysis on the pump and on the Y-shape tube are conducted respectively, which makes preparation for theoretical calculation of the flow rate.In the aspect of experimental research on VPPYT, based on different purposes, several groups of experiments are conducted by different test methods. On the one hand, the experiments verify the validity of the formula of flow rate; on the other hand, working performance of the VPPYT is further studied. Additionally, the positions of the two fluid levels of the pump in the especial experiment are recorded by using a high-speed-camera system, and then a curve of deviation between the two fluid levels changing with the time can be obtained. After that, the curve is studies by using fractal knowledge, and the induction and explanation for the result pattern from this explosive research are derived at last. As mentioned above, this research indicates that valveless piezoelectric pump with Y-shape tubes can overcome and avoid the shortcomings of generating large area of vortex and onflow, and has simple structure easy for miniaturization and integration, so it can be applied in the fields of medical care such as blood transfusion.