Numerical Simulation Of Current-Induced Vibration Of A Single Confined Cylinder Generated By Ocean Current Energy

With the rapid development of the global economy,countries all over the world are facing the problem of the increasingly insufficient renewable resources of the earth.Finding alternative green energy has become the key development direction of many countries.Among many new types of renewable energy,ocean current energy is favored by energy developers in various countries because of its large scale,wide distribution and abundant reserves.At present,the utilization of ocean current energy mainly adopts the mode of underwater turbine,but the starting flow rate of underwater turbine is more than 2m/s,and its application is limited.Therefore,low-flow current energy generation based on flow-induced vibration technology has gained more attention and development.Based on the study of the principle of single-constrained cylindrical ocean current vortex-induced vibration power generation,the numerical simulation of CFD is carried out by establishing a single-constrained cylinder physical model,and the numerical simulation results are analyzed.The developed parameters of the double-degree-of-freedom cylindrical vibrator vortex-induced vibration energy-carrying efficiency analysis software were used to analyze the relevant parameters.The main contents of this paper are as follows:(1)In this paper,a novel single-constrained cylindrical device is used to transform the model into a single-cylinder flow and fluid-solid coupling vibration problem.The NS equation is used as the governing equation for the incompressible viscous fluid,and the single-constraint cylinder is used by the fluid software CFX.The vortex-induced vibration is numerically simulated.Two kinds of Reynolds numbers(Re=224,3900)are selected to simulate the single fixed cylindrical flow and the elastic support rigid single cylinder in the incompressible viscous fluid.In the numerical simulation study of the cylinder,the results of single cylinder force cloud diagram,velocity distribution map,pressure coefficient,and rising resistance coefficient are obtained.The correctness of the model is verified by comparison with previous simulation results.In the single-cylinder fluid-solid coupling simulation calculation,the results of cylindrical force,displacement time history curve,lift resistance coefficient,vorticity map,etc.are obtained,and compared with the results without coupling,the results obtained are compared with the predecessors.It is more consistent,indicating that the method adopted in this study is reliable.(2)By simplifying the analysis of the physical model and combining the two-degree-of-freedom vortex-induced vibration to obtain the energy formula,the main parameters of the single-constrained cylindrical vortex-induced vibration are analyzed.The vortex-induced vibration energy acquisition of the double-degree-of-freedom cylindrical oscillator is developed by Matlab language.The analysis software verifies the reliability of the software by comparing the results of previous experiments.Then calculate a variety of working conditions,respectively calculated the damping ratio ?,mass ratio m*,mass damping ratio m*? on the single-constrained cylindrical vortex-induced vibration energy conversion efficiency ?,according to the conditions of the energy conversion efficiency Excellent value range.It is calculated that the different damping ratios and different mass ratios m* have a greater influence on the energy conversion efficiency ?.The energy conversion efficiency can be maximized according to the selected parameter range.In this paper,the numerical simulation of the current induced vibration of a single-constrained cylindrical ocean current is verified,and the feasibility of the device is validated.In the future,a suitable energy harvesting converter can be used,and then combined with the power transmission device to achieve large-scale utilization.This way uses ocean currents.