Numerical study of structural parameters influencing flow in a lunular valveless pump.

Piezoelectric pumps are widely applied in medical transportation, bioengineering, and mechanical lubrication. However, the backflow phenomenon of the valveless piezoelectric pump is more prominent. Therefore, this paper designed a lunular piezoelectric pump to reduce the backflow. The three-dimensional flow field of the piezoelectric pump was analyzed using ANSYS Computational Fluid X. Based on the numerical results, the design of the lunular piezoelectric pump was improved, and a new model of the piezoelectric pump with better performance was developed. A prototype was made, and an experimental verification was carried out. The experimental results show that the maximum flow rate per unit area is 404.812 µl/min and maximum back pressure is 22.3 cmHO, which achieves the optimal performance of the pump and verifies the rationality of Computational Fluid X simulation. Thus, the performance of a pressure pump with low driving frequency can be predicted by Computational Fluid X simulation, and the structural optimization method is reliable. This research can help to broaden the application of the piezoelectric pump.