Vibration Analysis And Flow Field Numerical Calculation Of The Piezoelectric Valve-Less Micropump

Micro-fluidics technology (develop on the base of micro-electronics, micro mechanics, biology engineering and nanometer technology) is defined as technologies focus on controlling, manipulating and inspecting complex fluid under micro-scale. As an important branch of Micro-electro-mechanical System (MEMS), it is much quicker and cheaper to utilize than the current technology and has been applied in many fields, among them the micro-pump is the most important one of basic equipments. This research mainly focus on the theoretical analysis to the micro-pump, the fundamental equations of diffuser/nozzle model and piezoelectricity actuate micro-pump membrane deformation model were constituted, then the analog computation was done to micro-pump membrane deformation model and the three dimensional flow field of the valve-less micro-pump through the ANSYS software. First the mathematical model of the diffuser/nozzle was built, the principle of choosing the structure parameters and corresponding computation methods of the damping coefficient were discussed. Then through the finite element method analysis to the flow channel by the software of ANSYS/FLOTRAN CFD, the velocity and pressure distribution and influence curve of flow arose by changing the structural parameters were got; and after formatting the finite analysis model of the micro-pump membrane, the membrane deformation and change in velocity was analyzed by the finite element direct coupling analysis, and on the basic of the analysis the membrane deformation curve arose by thickness, shape of itself and actuated voltage as obtained, then the modal analysis to the micro-pump membrane was done, the inherent frequency was computed out; the three dimensional flow field model of the valve-less micro-pump was constructed by the finite element indirect coupling analysis and the pressure contour and velocity vector graph was obtained, on the basic of former result the flow characteristic of the micro-pump system can be recognized. The research result can be used to make the design of the micro-pump more reasonable.