Simulation Analysis And Experimental Research Of Resonant Air Piezoelectric Pump Based On Synthetic Jet

As a new type of micro gas piezoelectric pump,air piezoelectric pump based on synthetic jet which can pump gas has been widely applied in active cooling,gas supply,power driving and many other areas.With its microminiaturization,simple construction,long lifespan,high efficiency,and easy digital control,it is also commonly available in heat dissipation of LED,carriage communication installations,auto-mobile electronics,computers,solar energy,household electrical appliances and other products.In this paper,a resonant air piezoelectric pump based on synthetic jet is designed,which is based on the National Natural Science Foundation “Design Theory of Fluid Dynamic Coupled Flexible Actuator Driven by Piezoelectric"(Item no.51405189).Combination of vibration of the piezoelectric vibrator with that of the flake structure containing a jet hole makes it possible to resonate within the whole system,thus the function of pumping gas is realized.This pump has the advantages of small volume and large flow rate.There are mainly two structures: single vibrator and dual vibrator.The single vibrator structure involves vibration of only one vibrator,thus it is of low energy consumption and simple structure.The dual vibrator structure involves vibration of two piezoelectric vibrators,hence it is of stronger output capacity and greater flow.The detailed contents of this paper are as follows:In the structure of the pump,ordinary circular piezoelectic vibrator and that with a jet hole are one of the most important drive components.The ANSYS simulation analysis of modal and statics aboat vibrator can help us choose the test frequency.By comparison,selecting the first-order mode of vibration of the ordinary piezoelectric vibrator,the natural frequency of the vibrator is 4281.9 Hz.Selecting the first-order mode of vibration of the piezoelectric vibrator with a jet hole,its natural frequency is 3992.7 Hz.Finally,the two kinds of vibrators are measured at different frequencies,which provides a reference for the application of the excitation in the simulation of the dual vibrator structure.Single vibrator structure use one vibrator to drive the pump,the copper sheet make a forced vibration.The experimental study of single vibrator structure obtaines four parameters: cavity height 0.8mm,pump chamber height 0.3mm,jet hole diameter 0.7mm,outlet diameter 1.0mm.When the frequency of the system is 3.9KHz,the flow of the structure reaches 1226ml/min..Measuring the displacement of copper sheet and vibrator,the displacement curves are all sinusoidal and having a phase difference.The simulation and analysis of the dual vibrator structure are carried out by using the multi physical field simulation software,and the air flow field,air velocity and air outlet flow rate are analyzed by using the fluid solid coupling interface for getting the specific movement of the air.Due to the parametric analysis of four parameters(cavity height,pump chamber height,jet hole diameter,outlet diameter)in the case of resonance,the maximum flow rate can reach 2110ml/min.For the experimental analysis of the dual vibrator,the parameter optimization experiment and the displacement measurement are carried out.The four parameters : cavity height is 0.6mm,the pump chamber height is 0.3mm,the jet diameter is 0.8mm,the outlet diameter is 1.0mm.When the frequency of the system is 3.9KHz,the flow reaches 1511ml/min.Compared with single vibrator structure,the dual vibrator's flow increases 23%.The displacement of two vibrators of the dual vibrator structure is measured,and the displacement curve shows that the two vibrators have no phase difference under the same excitation.Compared with the single vibrator structure,the amplitude of vibrator in dual vibrator structure is samller but the flow become larger.So it shows that eliminating phase difference can improve flow.