| With the development of science and technology and the progress of manufacturing technology,aerospace,biomedicine,fine chemistry,and other fields have put forward higher requirements for microfluid transport,which greatly promotes the development of micropump.The piezoelectric micropump driven by piezoelectric materials has the characteristics of fast response,high energy density,high integration,and no electromagnetic interference.Therefore,it has broad application prospects in microchemical mixing,fuel cell,biological detection,insulin injection,and other fields.In the study of fluid mixing,the piezoelectricity pump is mostly used as a driving device to drive microfluid mixing in the external mixer,but there are few studies on the internal mixing of the piezoelectricity pump.It is beneficial to simplify the flow of a microfluidic mixing system if the piezoelectric pump is used to drive and mix simultaneously.In practical application,the mixing of two liquids is often not simply equal proportion mixing.In view of this situation,based on the structure of the double cavity parallel piezoelectric pump,a passive valve type double cavity piezoelectric mixing pump is designed,and a series of experiments are carried out.The specific work content is as follows:1.Piezoelectric vibrator is the most important component of the piezoelectric pump,its performance directly determines the output performance and operational reliability of the piezoelectric pump.The piezoelectric materials used in the driving element piezoelectric vibrator are summarized,the basic working principle of piezoelectric vibrator is described,and the influence of various performance parameters on piezoelectric materials is explained.The different vibration modes and constraint modes of piezoelectric vibrators are analyzed and appropriate piezoelectric vibrators are used.2.Based on the working form of double cavity parallel piezoelectric pump,a passive valve type double cavity piezoelectric mixing pump is proposed to realize the variable proportion mixing of liquid;The components,connection and fixing methods of the piezoelectric pump are introduced,and the working principle of the passive valve type double cavity piezoelectric mixing pump is analyzed.The internal energy loss of the passive valve double cavity piezoelectric mixing pump is analyzed theoretically,and the key structural parameters are designed.Through simple simulation analysis,the feasibility of the designed structure in liquid transportation is verified.3.Making the passive piezoelectric hybrid pump valve type double cavity of experimental prototype,structures,experimental test system,the performance of the experimental prototype of the experiment test,the output flow rate and the relationship between the driving voltage and driving frequency,with the increase of frequency,output flow first increases then decreases,and the change of the output pressure is not big.Experimental tests were carried out on several experimental prototypes with symmetrical structures on the left and right sides,and the results show that the working frequency of the piezoelectric pump is between 20 Hz and 200 Hz,and the output flow is the maximum when the pump cavity height is 0.5mm,which can reach 96g/min.4.This paper analyzes theoretically the influencing factors of piezoelectric pump liquid mix proportion,pressure pumps on either side of the pump cavity through experiments to explore the different heights of liquid flow on both sides of the input,the influence of the inlet pipeline flow resistance on both sides not to enter the influence of fluid flow on both sides at the same time,and on both sides of the piezoelectric vibrator seal groove depth at different influence on liquid flow on both sides of the input,prototype of The piezoelectric pump with an asymmetrical structure is tested.Experimental results show that the pressure pumps on both sides of the different seal groove depth and the depth of the pump cavity will be made on both sides of the input flow,change the circulation of the side entrance pipe also can make two different entry input flow,through some of the parameters of the asymmetric structure setting,again by adjusting the frequency and voltage of the drive signal can achieve arbitrary proportion adjustment,it has a good reference value for the study of adjusting mixing ratio. |
PDF Full Text Request