Efficiency analysis and simulation studies of a piezoelectric micropump with novel microvalve

A novel microvalve structures with adding vortex areas in profile which looks like the saw-tooth (STT-and ST- microvalves) have been designed, and the new efficiency model for the valveless micropump with piezoelectric actuator has been presented in this paper. For comparison purposes, fluidic simulations of three dimensions have been performed to the novel saw-tooth microvalves and the traditional diffuser/nozzle microvalve with CFD (Gambit and Fluent) software under steady conditions, respectively. The steady efficiencies under two limit conditions (the max flow rate at zero pressure head and the max pressure head at zero flow rates) have been calculated. The characteristic curves of several microvalves have been drawn with mat-lab software. The results show that the pressure loss and flow rate confirm the expected changes which along with the increase of the main cross-section in both flow directions by passing from the standard microvalve to the ST- and STT-ones, and the steady efficiency of the STT-microvalve is higher than that of other microvalves. Finally, in order to testify the result of simulation, the micropumps with STT-microvalve and S- microvalve have been fabricated. Through experiment it proves that the performances of the micropump with STT-microvalve are excelled than the S-microvalve because of the presence of the vortex areas and the taper.