Design and experimental verification of variable-structure vortex tubes for valveless piezoelectric pump translating high-viscosity liquid based on the entropy generation

Abstract

To transfer the high-viscosity biological fluid and improve the outflow, four valveless piezoelectric pumps, with variable structure vortex tubes, has been proposed. The output performances of each valveless piezoelectric pump were tested in subsequent experiments, which proved that some vortex tubes can strengthen the diversion characteristics, thereby improving the output performance of the valveless pumps. Numerical calculations and experimental methods were used to compare the flow characteristics of the vortex tubes. A numerical solution to obtain entropy generation of vortex tubes’ flows was presented based on entropy generation theory. The results presented that the energy loss of the vortex tube with structure of changed axial tube, was the smallest, while its cut-off characteristic was the best. During transporting experiment of the high-viscosity fluid, the valveless PZT pumps delivered glycerin aqueous solution with 5.041 cps, which validated the transportation ability of a certain viscosity of bio-viscous fluid. The application of valveless PZT pumps in high-viscosity viscous fluid was expanded by valveless piezoelectric pumps with variable structure vortex tubes. Moreover, such work will provide reference for the improvement of the micro-pump performance, and further promote the application of the micropumps in the biomedical field.