Aerodynamic design and analysis for offshore wind turbine blade model

Model experiments are essential for designing and analysing offshore wind turbines. During the scaling process of the model, the rotor thrust significantly decreases due to the Reynolds number effect. As wind turbines increase in size, blade length also gradually increases. The scaling ratio of the model decreases due to laboratory size constraints, affecting the structural loading characteristics. Therefore, this study performs an aerodynamic design for model blades, considering the Reynolds number effects and geometric dimensions. The optimised blade satisfies the scaled model's thrust requirements when its length is shorter than the scaled prototype blade. We employed the low Reynolds number airfoil SG 6043 to optimise the model blade. The geometric parameters of the optimised blades were calculated using the blade element momentum theory and pattern search method. Wind tunnel experiments were conducted on the optimised blade to analyse the variation characteristics of rotor thrust. The research results show that the numerical calculation results of rotor thrust generally align with the experimental results. The rotor thrust of the optimised blades was significantly enhanced, meeting the scaled model's thrust requirements. The error between the optimised blade's rotor thrust and the scaled target value is less than 2 %.