Research On The Aerodynamic Performance Of Vertical Axis Wind Turbine With Trailing Edge Of Blade Tip

With the development of social economy,people are more and more aware of the importance of environmental protection,and the country also vigorously advocates the development of sustainable use of new energy,wind,nuclear,solar and other representative new energy has been paid attention to and rapid development,and is gradually replacing traditional energy to serve humanity.Wind energy use is mainly the wind energy into electrical energy to use,and main equipment of wind turbine is in using wind energy,wind turbine is divided into two categories,wind turbines with horizontal axis and vertical axis wind turbines,relative to the horizontal axis wind turbine,because of the complexity of the flow field and vertical axis wind turbine development relative lag,but in recent years,in the state of the new energy,and in contrast,the study of horizontal axis wind turbine are relatively mature,and vertical axis wind turbines research relatively lags behind,but also has low noise,no drift device,low production cost advantages,vertical axis wind turbines has got rapid developmentAmong the researches on wind turbines at home and abroad,there are relatively mature researches on the installation of blade tip winglets for horizontal axis wind turbines,while there are relatively few researches on the installation of winglets for vertical axis wind turbines.This paper studies the installation of trailing edge winglets for h-type vertical axis wind turbines.According to literature review,the location of tip vortexes generated by vertical axis wind turbine blades is mainly within 5%of the blade tip.By optimizing this part of the position,the generation of tip vortices can be suppressed to a certain extent,thus reducing the losses caused by tip vortices and improving the efficiency of wind turbines.In this paper,winglets are added to the trailing edge of h-type vertical axis wind turbine blades to study the aerodynamic performance of the wind turbine.In this study,winglets are added in two forms streamlined winglets designed according to the flow direction of the trailing edge of the blade,and a more conventional flat fan type winglets.Three sizes were used for each winglet to optimize the position between 3.3%and 10%of the blade tip.The changes of aerodynamic performance of blades with trailing edge winglets compared with those without winglets were analyzedCFD numerical simulation and wind tunnel experiment were used to analyze the vertical axis wind turbine with trailing edge winglet.Through CFD numerical simulation analysis of torque coefficient,output power and tangential force of blades with trailing edge winglets,it is found that the output characteristics of blades with trailing edge winglets are improved compared with those without winglets.Winglet output characteristics of different sizes under different rotational speed increase,the output power can increase about 7%,the peak torque coefficient can increase about 11.96%,tangential force can increase about 15.21%,and through in the wind tunnel experiments of adding small wing trailing edge blade output power are verified,consistent with the results of numerical simulation.To add small wing trailing edge of blade after analysis found that the flow field in the wake velocity field can verify the position of the vertical axis wind turbine blades work mainly for middle leaves,and it can be seen that adding small wing trailing edge of the vertical axis wind turbine for wind energy absorption rate has a certain degree of improvement,and in observing blade trailing edge velocity field found that after adding winglet,blade trailing edge middle speed increase,the Bernoulli principle shows that trailing edge speed,reduced rear pressure,differential pressure increases,so as to lift the vane of improvement.Followed by a single leaf on the wind pressure distribution analysis of work area,found that after adding small rear wing,both inside and outside differential pressure increases,and the blade section pressure value was extracted,found that the blade surface pressure difference has a certain degree of ascension,and,after adding small rear wing,a maximum 11.04%increased pressure difference,and found that adding small wing trailing edge effects on the blade surface pressure difference from leading edge to trailing edge enhanced gradually,and velocity analysis.The vorticity field was then analyzed,and it was found that the vorticity of tip vortexes and wake vortexes generated by blades with trailing edge winglets was somewhat lower than that of those without winglets.In this paper,numerical simulation and wind tunnel experiment are adopted to analyze the output characteristics,velocity field,pressure field and vorticity field of a vertical axis wind turbine equipped with trailing edge winglets.It is found that the installation of trailing edge winglets has a positive influence on the aerodynamic characteristics of a vertical axis wind turbine.It can provide some reference value for improving the aerodynamic performance of vertical axis wind turbine.