A Fluidic Diode and Its Application to a Valveless Micropump

In this work, topology optimization was used to design a fixed-geometry fluidic diode of high diodicity, defined as the ratio of pressure drop of reverse flow to forward flow. Next, the fluidic diode was used in a valveless micropump. A three-dimensional and unsteady numerical analysis of fluid flow inside the micropump with the optimized diode was conducted by Computational Fluid Dynamics (CFD). Performance of a nozzle-diffuser type diode in the valveless micropump was also evaluated under the same conditions, for comparison. Both types of micropumps were fabricated and tested. The results show that the micropump with the designed fluidic diode can reach a flow rate of up to 33.5 ml/h, which is consistent with the simulation results and 2.2 times that of the nozzle-diffuser type micropump.