Research On Aerodynamic Performance Of Inverted Cone Vertical Axis Wind Turbine

With the carbon peak and carbon neutralization being incorporated into the overall layout of China’s ecological civilization construction,renewable energy including wind power has become the main direction of energy development in the new period.Wind power generator is an important equipment which converts wind power into mechanical energy and utilizes wind resources for human production activities.In recent years,vertical-axis wind turbine has attracted much attention of researchers due to its advantages such as acceptable wind from all directions,high turbulence adaptability,low manufacturing and installation costs,and installation near the ground.However,the unstable angle of attack during its operation results in the disadvantages of low utilization of wind energy and difficult self-start,and the traditional main shaft and connecting arm mechanism brings difficulties to the large-scale and pitch-variable design of vertical-axis wind turbines.This paper focuses on the research on the aerodynamic performance of wind turbine with inverted cone vertical axis.This is a new type of wind turbine,which removes the huge spindle and connecting arm mechanism,improves the structure stability and reliability,and is easy to install the propeller mechanism,so it has high research value.Firstly,through theoretical analysis method,the force condition during operation of inverted cone type wind turbine is studied,the dimension parameters of 2MW inverted cone type wind turbine are calculated,and based on the principle of hydrodynamic similarity,the judging conditions for aerodynamic similarity of wind turbines of different scales are deduced,and a similar experimental scheme for simulating operation process of large wind turbines with small experimental prototype is designed.Then,the 2MW inverted-cone wind wheel is simplified by referring to the dimension parameters calculated in theory.The aerodynamic performance of nine inverted-cone wind wheels with different structure parameters is simulated and analyzed by CFD method.The influence of structure parameters on the power coefficient,operation stability and low wind speed starting torque of wind wheel is studied,and the optimum tip-speed ratio of wind wheels with different structure parameters is obtained.The optimum power coefficient,maximum output power,power fluctuation amplitude,optimum starting azimuth angle and maximum starting torque coefficient are obtained,and the design criteria of the structural parameters of the inverted cone wind turbine are summarized.Finally,based on the similar experimental scheme designed above,an upside-down cone wind turbine test platform is built,which has the functions of adjustable wind wheel structure parameters,controllable running speed,measurable output torque and power,and wind tunnel test is carried out.The experimental results verify the feasibility of the principle of the chamfered cone wind turbine and the correctness of the simulation analysis,and design the pitch angle function,which creates the conditions for the experimental verification of the chamfered cone wind turbine in the follow-up study.