Research On Valveless Piezoelectric Pump With Parallel Connection Conical Spiral Cavity

The Piezoelectric pump has many kinds of advantage such as simple structure、low energyconsumption, etc. And it may widely used in Aeronautics and astronautics、biomedical、Micromechanical and so on.But now low efficiency、volatility、backflow and single function can always befound in the traditional valve-less piezoelectric pump. Just because of these disadvantages,theapplication of such piezoelectric pumps are greatly limited.Now by improving the helical flow tubeand the technology of tapered-flow-tube valve piezoelectric pump we put forward a kind of valve-lesspiezoelectric pump which has Multiple conical spiral cavities. And the conical spiral cavities are inparalleled. Such a new kind of valve-less piezoelectric pump can be used in mingling the liquid、heatdissipation and so on.We deduce a theoretical formula which can make a respond of the flow characteristics in theconical spiral flow tube flow characteristic researching.And by using the finite element we make aresearching on the fluid dynamics when the multi-rate fluid flowing back and forth in the conicalspiral flow tube of rectangular and circular cross-section.In such ways we find it can be made into anvalve-less piezoelectric pump by using the conical spiral flow tube; In the laboratory we made ameasurement of amplitude on condition that piezoelectric vibrator was giving empty load.At thesame time the equation between the pump cavity volume variation and the pump flow rate wasestablished.We can use these experimental data and equation to make a foundation in measuring thepump’s fluid traffic.By analysis the flowing characteristic、 the working principle when thepiezoelectric vibrator was synchronous and asynchronous working and simulating the flow fieldcharacteristic of the pump cavity we proving the ability of mixing and transmission of such apump.In order to identify that it can make a improving the working efficiency by choosingthree-cavity in parallel.We had exploring the output performance when the pump was working onone-cavity active、two-cavities active and three-cavities working. During the experiment we had madea test on the voltage and frequency which can have a great influence on the working performance.Wefound that the backflow phenomenon and the output ripple was reduced when the piezoelectricvibrator was working on asynchronous.