Research On Aerodynamic Characteristics Of Spiral Vertical Axis Wind Turbine

A wind turbine is a device that rotates wind as a driving medium and converts wind energy into electrical energy.Although the form of wind turbines is diverse,different types of wind turbines use their respective characteristics to improve their own output torque and power generation efficiency.The vertical axis wind turbine has been favored by many scholars due to its good aerodynamic performance,low starting wind speed,low noise,no wind direction limitation,no yaw device,easy installation and maintenance,and low maintenance cost.However,there are some shortcomings.Vertical-axis wind turbines have large fluctuations in the dynamic torque of the blades,dynamic torque oscillations severely destroy the stability of the rotor rotation spindle,and the power output of the wind turbine is unstable.The wind turbine performs aerodynamic studies to improve its output torque and wind energy utilization.The main contents of the paper's research are as follows:(1)Select the airfoil for the spiral vertical axis wind turbine,mainly including two-dimensional simulation of the NACA0009,NACA0012,NACA0015,NACA0018 airfoil under the established structural parameters and wind field environment,simulate and calculate the maximum lift-to-drag ratio,and determine the wing Select NACA0012.(2)Two-dimensional simulation of wind turbines with different number of blades in different wind field environments.Analysis of the wind turbines,pressure cloud diagrams,and pressure curve diagrams to determine the optimal number of wind turbine blades is 3,and wind turbines.The effects of the wake field on other wind turbines during rotation.(3)Spiral vertical axis wind turbines with spiral angles of 30°,45°,60°,90°,120°,and150° are selected and the tip speed ratio is 0.6,0.8,1.0,1.2,1.8,2.0,2.4.2.8,3.2,3D simulation with wind speed of 2m/s,4m/s,and 6m/s.Through the analysis of the output speed cloud map,pressure cloud map,turbulence viscosity cloud diagram and torque coefficient curve and wind energy utilization curve,the data is processed to obtain the maximum output wind energy utilization rate of 48.2%,to determine the best combination of parameters: wind speed of 6m/s,The tip speed ratio is 2 and the helix angle is 60°.(4)After researching spiral aerodynamic characteristics with different helix angles,four wind turbine wind angles(60°,90°,120°,150°)were selected to conduct wind tunnel tests.The output values were monitored and the wind speed and wind turbine speed were obtained.The relationship between the wind speed and the power of the wind turbine is calculated.The value of the wind energy utilization rate Cp is calculated and the curve is plotted.The maximum wind energy utilization rate is 38.2%,which is far from the theoretical value of59.3% of the wind energy utilization rate.It needs to be improved.(5)After determining the best combination of parameters,spiral-shaped vertical axis wind turbines of different heights are installed at different positions on flat-top buildings.By analyzing the velocity cloud diagrams of different sections in the two schemes,the spiral vertical axis wind turbines are determined.Determine the best installation distance.