Research And Design Of Valveless Piezoelectric Micropump Of Double Linkage Cavity With Tri-Vibrational Film

Microfluidic system is a technology of controlling, manipulating and detecting complex liquid in microcosmic size.Micropump is an important execution unit of microfluidic system,which indicates the developing level of microfluidic systems.Various types of micropumps have been developed,especially valveless micropumps with simple structure attract much more attention and have become focus of research in recent years.In this thsis,a new micropump is put forward named valveless micropump of an integration of double cavity with tri-vibrational film。Its main units consist of the double cavities, the double diffusers/nozzles beside the cavities, the top composite piezoelectric vibrators, the middle one which connects the double cavities together, and the nether one. The new micro-pump has the advantages with simple and compact structure, easy manipulation, and a high reliability as well as a remarkably improved life-span. Transferring liquid with fineness, large runoff and high efficiency could be realized in the new type micro-pump.The main research content as follows:(1)A new valveless micro-pump is put forward with its working principle introduced. The thesis also offers the elementary design of the controlling project, actuating mode of the new micro-pump. The figures of the composite piezoelectric vibrators, the diffusers/nozzles pipe, cavity of the micro-pump and the cushion chamber are also primarily designed.(2)Key parts working in the new type micro-pump are established-- simplified model of the composite piezoelectric vibrators, deducing the elastically crooked differential equations and the vibrating equations of the composite piezoelectric vibrators, giving static analysis and dynamic analysis on vibrator by using ANSYS software ,thus carrying out structural optimization on vibrator.(3)Some features of fluid flow under micro-scale are described. The thesis gives an analysis of the diffusers/nozzles pipe pressure loss coefficient and energy loss, deduces the runoff and efficiency of the diffusers/nozzles pipe and use FLUENT software conducting a finite element analysis for the diffusers/nozzles pipe, pump cavity and the cushion chamber ,optimizing its structural parameters.Research results provide a theoretical basis for the piezoelectric-driven valveless micro-pump structure design and have important reference value for the rationalization of the design of micro-pump.