Aerofoil Shape Design And Performance Evaluation Of H-rotor Vertical Axis Wind Turbine

With the continuous development of the social economy,human beings are facing increasingly serious environmental pollution and energy shortages.Therefore,the country strongly advocates the development and utilization of renewable energy.As a clean and renewable energy source,wind energy is more and more popular and favored by people in recent years.As an important device for converting wind energy into electrical energy,wind turbines are generally divided into two categories: Horizontal Axis Wind Turbines(HAWT)and Vertical Axis Wind Turbines(WAWT).After years of development,HAWT generator technology is relatively mature.Compared with HAWT generators,WAWT generators have gradually entered the eyes of research scholars due to their simple structure,easy installation and maintenance,high adaptability,no yaw device,and simple blade manufacturing.People began to invest a lot of resources to explore WAWT.This paper takes the H-type Vertical Axis Wind Turbines(H-WAWT)as the research object.The main research categories are as follows:(1)Based on the leaf element theory,the operating mechanism of the H-WAWT was studied with deeply,and the general change law of the blade angle of attack and the aerodynamic force acting on the blade under different azimuth angles was obtained;According to the actual H-WAWT structure parameters,using the CFD method to establish a two-dimensional H-WAWT fluid calculation model,Correction of numerical simulation results based on blade aerodynamic force and power coefficient correction model,and combined with the wind tunnel test data to verify the accuracy and feasibility of the numerical simulation in this paper;(2)This paper uses variable parameters method was used to research the influence of parameter configuration of H-WAWT on its aerodynamic performance,and the influence of different blade installation angle,wind wheel radius,blade number and blade chord length on the output capacity of H-WAWT was obtained.Provides a theoretical basis for the design of structural parameters of H-WAWT.(3)Considering that the blade is one of the key components of the wind turbine,this paper proposes a method combining class function and B-spline function to characterize the aerodynamic shape of the airfoil,combined with the particle swarmoptimization algorithm and coupled with the airfoil aerodynamic performance prediction RFOIL software for airfoil aerodynamic shape optimization of H-WAWT.In the optimization process,in view of the wide range of angle of attack of the H-WAWT blades,the effects of different attack angle ranges on the optimization of the aerodynamic shape and wind energy utilization of the airfoil are proposed.The sum of tangential force coefficient at each angle of attack is used as the objective function of blade airfoil optimization.The optimized airfoil is compared with the initial airfoil,and the superiority of the optimized airfoil is discussed from the wind energy utilization rate,torque coefficient of a single blade,vorticity distribution,velocity distribution and pressure distribution.Research shows that the aerodynamic performance of the new H-WAWT has been greatly improved,and the maximum wind energy utilization rate has increased by 8.45%.This study provides a reference for the design of the H-WAWT structural parameters and the optimization design of the blade airfoil aerodynamic shape,which has certain engineering application value.