Research On The Influence Of Adding Windshield Baffle On The Aerodynamic Performance Of H-type Vertical Axis Wind Turbine

H-type vertical axis wind turbines are favored by people because of their simple structure,easy installation and maintenance,low operating noise and other advantages,but because of the internal flow field is more complicated,since the start difficult and actual wind energy utilization rate is relatively low at present,to improve the performance of the vertical axis wind turbines,in this paper by NACA0021 small two blade vertical axis wind turbines,is put forward in the operating area outside the installation method of the windshield baffle,through theoretical analysis,numerical simulation and experimental study,to improve wind turbine operation flow field,its wind energy utilization rate and start-up performance.The main research contents and conclusions of this paper are as follows:1)For NACA0021 small vertical axis wind turbines,using the orthogonal experiment design method,to wind energy utilization differenceΔC_p and moment coefficient during the week of volatility as the research target,research the distance of the windshield baffle length,horizontal layout,vertical distance and Angle of deflection and so on four structural parameters on the influence of wind turbine aerodynamic performance.The results show that the deflection Angle has the greatest influence on the aerodynamic performance of the wind turbine,while the length has the least influence.2)According to the order of the influence proportion of each parameter from small to large,the simulation calculation shows that the best horizontal layout distance of the windshield baffle is R,the vertical layout distance is 2.5R,the length is 0.9H and the deflection Angle is 25°.Compared with the prototype wind turbine,the wind energy utilization rate of the wind turbine with windshield baffle is increased by 5.46%.According to the flow field analysis,the windshield baffle can improve the velocity of the flow field in the operating area of the wind turbine,increase the pressure difference between the two sides of the blade,and shorten the wake area of the wind turbine.3)To install the best parameters of the windshield baffle wind turbine,wind turbine by Fluent simulation monitoring stress state,offered to amplitude,mean and coefficient of variation for the evaluation of the fluctuation in wind turbine aerodynamic load parameters,studied the wind machine spindle before and after adding together the windshield baffle synthetic power fluctuations,the simulation results show that adding poly windshield threatening the wind machine spindle synthetic power fluctuations.For the starting time of wind turbine,the UDF simulation method is used to study the starting process of wind turbine.By comparing the running speed curves of wind turbine before and after installing windshield baffle,it is found that installing windshield baffle can effectively shorten the start-up of wind turbine.4)The scale model wind turbine model was prepared by 3D printing technology,and a wind turbine test platform with windshield baffle is built.Wind tunnel tests are carried out on the prototype wind turbine and windshield baffle wind turbine with the best parameters.The test results show that the installation of windshield baffle can effectively improve the aerodynamic performance of the wind turbine and shorten the start time.Before and after installing the windshield baffle,the load voltage of the wind turbine increased by about13.38%,the load power increased by about 28.44%,and the starting time shortened by about 23.1%.The test results can verify the effectiveness of installing the windshield baffle.