Theoretical And Simulation Research Of Flow Induced Vibrating Piezoelectric Energy Collector

With the development of microelectronics and low power consumption technology,the power consumption of various sensors has been continuously reduced,making it possible to power all kinds of miniature sensors by collecting weak surrounding energy.Therefore,energy harvesting technology has become a hot research direction nowadays.Acoustic sensor power consumption is not large,but the replacement of acoustic sensors battery is very difficult.Acoustic sensor network is an extension of the land-based sensor network,and its sensor power supply problem is the bottleneck of the development of acoustic sensor network.Among the many power supply solutions,flow-induced vibration piezoelectric energy harvesting technology has become an important solution to the power supply problem of acoustic sensors.However,the flow-induced vibration piezoelectric energy harvesting technology has many characteristics such as multi-disciplinary knowledge and multi-field coupling,which makes flow-induced piezoelectric energy harvesting technology one of the most challenging research fields in the field of renewable energy.The dissertation firstly introduces the research background,and then presents the research status of piezoelectric vibration energy harvesting technology from four aspects: flow induced vibration,piezoelectric energy collection,flow induced vibration piezoelectric energy collection structure and energy collection circuit.Then,the contrast of the functions of the piezoelectric energy harvesting simulation tools is done from different perspectives.Based on the research status quo,this paper presents a structure of piezoelectric vibration energy collection using underwater induced vibration.The structure puts the bimorph piezoelectric cantilever into the flexible light pipe in the axial direction,the circular pipe stands in the fluid,and the axial direction is perpendicular to the incoming flow direction.The neutral plane of the cantilever beam in the cylinder is parallel to the flow direction.So that the use of flow-induced vibration of the flexible cylinder cyclical bending vibration,driven by the piezoelectric cylinder cantilever vibration and generate electrical energy.Then,the fluid-solid coupling motion of the piezoelectric vibration energy collecting structure is studied and analyzed by the method of mathematical modeling.The theoretical deformation response curve of the fluid-solid coupling is simulated by MATLAB,and then the piezoelectric coupling equation is described.Then a detailed fluid-solid coupling simulation and analysis of the new piezoelectric energy harvesting structure was carried out.First of all,the simulation flow of ADINA single tube is introduced in detail.On the basis of the comparison,two flexible tubes and a flexible tube with a rigid cylinder are simulated.The simulation results show that the structure of a flexible tube with a rigid cylinder is more ideal.In order to find the optimal position for placing the flexible tube behind the blunt body,the simulation of a rigid cylinder with three flexible tubes is performed.The simulation results show that the second flexible tube behind the rigid cylinder(16cm from the center of the bluff body)has large and stable vibration response.Based on this,a series of simulation experiments have been carried out to change the inlet velocity of the fluid field.The simulation results obtained have the same trend with the experimental values of other scholars.Then the electromechanical coupling simulation was carried out,which consists of piezoelectric coupling simulation and energy harvesting circuit simulation.The structure of the bimorph piezoelectric cantilever was established by using ADINA simulation software.A deformation was applied to the free end of the cantilever to obtain the voltage distribution of the piezoelectric patch.At the same time,based on the piezoelectric simulation,the second development of the piezoelectric simulation was implemented by using the Python language.The optimal vibration response curve obtained by the fluid-solid coupling was input into the piezoelectric simulation program for piezoelectric simulation.Finally,the results obtained were 85 V,9Hz AC voltage response.Then the energy harvesting circuit was studied.The simulated open circuit voltage was taken as the input voltage of the energy harvesting circuit,and the energy harvesting efficiency of the standard energy harvesting circuit was 36.18%.At the same time,the energy harvesting circuit was simulated using the LTC3588 chip and some experimental studies were carried out.The simulation results are in good agreement with the experimental results,confirming that the flow-induced vibration piezoelectric energy collector can be used in practice.Finally,the experimental platform of the flow-induced vibration energy harvester was designed.Firstly,the design of the experimental system was introduced as a whole.Then the design work was carried out from three aspects: the water level automatic adjustment water circulation system,the pipe speed measurement system and the flexible tube vibration video acquisition system respectively.In this paper,a series of researches on flow-induced vibration piezoelectric energy harvesting are carried out,which provide references for the practical preparation of flow-induced vibration piezoelectric energy harvester.It is of great significance to the development of acoustic sensor networks and the progress of renewable energy technologies.