Design And Research Of Miniature Wind Energy Generator Based On Impinging Jet Instability

With the rapid development of microelectronics in recent decades,the working speed of microprocessors has increased by about one thousand times compared with that before.However,in the traditional sense,the energy density of chemical batteries increased only twice in the same period.At present,providing enough power for wireless devices such as sensor nodes is one of the main bottlenecks hindering their further miniaturization.Among them,the miniature wind energy collector,which obtains energy from the environment and converts it into electricity,has become a hot spot in the research of micro-energy in the world.In this paper,numerical simulation and experiment are combined to study the coupling characteristics of flow stability and structural vibration of impinging jet vibration wind turbine.The research contents mainly include the following three aspects:In this paper,based on ANSYS Workbench multi-physical field software platform and jet as excitation source,the vibration model of edge prism-elastomer is established by numerical simulation method.Using Transient Structural and CFX modules,the influence parameters of fluid-solid coupling vibration characteristics of the vibration model are studied.Based on this research,the edge prism-elastomer coupling vibration enhancement technology is studied.The conclusions are as follows: the distribution of equivalent stress and strain at the fixed end of a cantilever beam is larger than that at other locations in the vibration state;with the increase of wind speed(0 ~ 30 m/s),the vibration amplitude and frequency of the cantilever beam increase;the vibration amplitude between the nozzle outlet and the free end of the cantilever beam is more obvious than that under other conditions when the distance between the nozzle outlet and the free end of the cantilever beam is 110 mm.Secondly,the design of wind energy acquisition system based on impact jet vibration is carried out.A new type of cantilever piezoelectric vibration wind energy acquisition device structure is proposed,and a micro wind generator is composed of PVDF piezoelectric transducer.In order to test the output performance of the designed miniature wind energy collector,an experimental platform and a test system are built independently.Finally,by means of blowing experiment,the working characteristics and output characteristics of the micro wind energy collector based on the instability of impinging jet at different wind speeds,the ratio of width to height at the outlet of the jet,the distance between the free end of the PVDF piezoelectric plate and the outlet of the jet,the blunt body and the load are experimentally studied.The experimental results show that the PVDF piezoelectriccantilever beam can oscillate periodically when the wind speed ranges from 6 to 14 m/s,and it can obtain stable output power in the case of resonance.When the ratio of width to height of the jet outlet is 8.3,the distance between the free end of the PVDF piezoelectric sheet and the jet outlet is 80 mm,the maximum output power is up to 83 uW.The experimental results will provide a new design idea for small-scale vibration wind turbines.