Model Experimental Study On Hydrodynamic And Power Characteristics Of Vortex Induced Vibration Water Flow Energy Conversion Device

VIV aquatic clean energy as an emerging clean energy technology which extract energy from the flow field based on vortex-induced vibration phenomena.VIV energy basic generating devices is composed of a vibrating body with an elastic support and without dam.In certain river or sea area,the spatial array is composed of several same or different vibrating bodies forms the river or ocean power plant which also has good size scalability.The traditional method of hydro power generation is to use hydroelectric turbines,and need at least 2m / s flow rate can achieve a better economic benefits,but the VIV aquatic energy technology can be used to extract water flow energy only in the flow rate of 0.25m/s.The energy technology also has the following advantages: have high density energy;do not affect the surface traffic;be friendly to marine life;low maintenance costs;be robust system;have long life.These characteristics of VIV aquatic energy show that the technology can be widely used in rivers,seas,oceans,tides and other flow with broad prospects for development,it is necessary to carry out research on vortex induced vibration water flow energy conversion device to the global renewable clean energy development and sustainable development strategy which has important scientific and engineering significance.This paper firstly summarizes the current situation of VIV and its energy conversion device at home and abroad,the basic theory of VIV and the principle of water flow energy conversion are introduced.The mathematical equations based on energy conversion is established,including vibration model,generator model,energy transfer model,damping analysis and the mathematical expressions of output power and energy conversion efficiency.A series of important dimensionless parameters are obtained by dimensional analysis and similarity analysis.In the physical model test,which introduces some important experimental equipment and instruments,and then through the collection and analysis of the test data,the conclusions are as follows: the VIV locking range of the device 5-7.7,then in the locking range,when the amplitude ratio of the device is 1.2,the frequency ratio can be as high as 1.15;the relationship between the lift coefficient and drag coefficient of the two frequency and frequency locking phenomenon are observed;the device has a maximum output power of 1.5w in the range of flow velocity 0.485m/s-0.664m/s and the maximum energy conversion efficiency can reach 0.30 only when the flow rate is 0.485m/s,and the experiment results are compared with the foreign scholars' research results,it is proved that the test device has a certain reference value.Finally,by comparing the characteristics of the device under the condition of acceleration and deceleration,proved that the hysteresis will strengthen the vortex induced vibration response of the device in a certain range.This paper based on the theoretical analysis and model test of the VIV water flow energy conversion device,some available data and conclusions are obtained,which provides a certain direction for the promotion and application of the new clean energy.In the end of the paper,the author gives the summary and prospect of the research content of this paper.