Research on a valveless piezoelectric pump with inner concave triangle structure

Valveless piezoelectric pumps have the advantages of simple fabrication, lower cost, and high cleanliness. Valveless piezoelectric pump compared with valved piezoelectric pump, the backflow phenomenon is more serious, which greatly limits the application in reality. In this paper, a valveless piezoelectric pump with an inner triangle structure is proposed to increase to the resistance of reverse flow by the inner concave triangle structure to achieve the purpose of reducing backflow. The factors influencing the efficiency of forward flow were analyzed by theoretical modeling. Then, the flow resistance of this valveless piezoelectric pump is numerically calculated by finite element analysis. Finally, the output performance of the pump was experimentally investigated. The experimental results show that when the number of concave triangles in the flow channel are two, the inclination angle (B) are 45°, and the height are 3 mm, the performance of this valveless piezoelectric pump is optimal, and the flow rate and pressure reach 190.86 ml/min and 673 Pa respectively. This study provides some valuable insights to improve its performance and practice. This piezoelectric micropump could generate large flow rates and output pressures with great advantages in the fields of mechanical lubrication and biomedicine.