Study On The Influence Of Wind Turbine On The Characteristics Of Regional Atmospheric Boundary Layer Based On Large Eddy Simulation

The wind power to save energy,reduce pollutant emissions and other advantages in developed rapidly at home and abroad,the wind power generation brings positive environmental benefits at the same time,influence on the structure of atmospheric boundary layer,the local climate of the wind turbine operation process has caused a high degree of concern in academic circles.Wind turbine is the core equipment to transform wind energy into electric energy.When it runs,it generates wake flow and causes energy loss.Therefore,studying the influence mechanism of wind turbine operation on the atmospheric boundary layer characteristics is very important for optimizing the design of wind energy projects.By establishing the model of wind turbine and the surrounding flow field,the unsteady atmospheric turbulence theory combined with large eddy simulation method,the UDF function was two times the development of Fluent software,the loading of atmospheric boundary layer wind profile and temperature distribution function,boundary layer characteristics influence on the regional atmospheric boundary of wind turbines,the following work has been done:(1)the analysis and research of wind turbine operation mechanism of the influence of the characteristics of atmospheric boundary layer,the vortex structure and wake flow characteristics analysis of wind turbines,and explores the effects,the wake on atmospheric boundary layer meteorological factors the results show that the wind turbine will produce similar vortex spiral structure,vortex structure is divided into the center of vortex,Ye Jianwo and vortex three parts,wind turbine generating wake are the main factors leading to the change of the characteristics of atmospheric boundary layer,wake disturbance reduces the atmospheric energy in the atmospheric boundary layer,turbulent kinetic energy increases,not only broke the original distribution of the atmospheric boundary layer structure,characteristics and the balance of energy,while the speed in the near wake region of serious losses,four severe turbulence,wind speed and turbulence intensity peak exists in the near wake flow velocity profile and turbulent kinetic energy distribution curve They correspond to the tip vortices of the tip of the leaf and the central vortices of the impeller.(2)Wind turbine comparative analysis on the variation of bo ttom boundary layer region characteristic in different temperature stratification conditions,wind speed,wind shear index,turbulent kinetic energy,momentum and heat fluxes found in different stratification contrast: air after wind turbine after the change trend was similar,but did not change with the stratification caused by the numerical slightly at the same time,due to the vertical temperature in different stratification distribution caused by different wind turbine wake effects on the temperature in the atmospheric boundary layer in the different temperature stratification changes on the comparison is obvious,and the different stable layer near wake region temperature range around the atmospheric temperature is very smal.(3)According to the change of the underlying surface when the wind turbine wake effects on the characteristics of atmospheric boundary layer is studied,the variation trend and distribution characteristics of velocity,temperature,turbulence,wind shear,momentum and heat flux to illustrate the influence of wind turbine operation,gradually decreases with the exchange of momentum between the surface roughness increases the surface and the atmosphere.The heat exchange rate gradually increased,the recovery rate decreased gradually;the turbulent kinetic energy along with surface roughness increases the spatial non-uniform distribution characteristics is more obvious;the temperature along the vertical direction is slightly reduced,and with the increase of surface roughness degree of influence and the deepening of.