Study of Horizontal Axis Wind Turbine Blade in Virtual Wind Tunnel Simulator

Abstract

The article presents a 3D model analysis of a single blade for a horizontal axis wind turbine (HAWT). The analysis focuses on calculation of the wind pressure on the blade under different wind velocities and directions within the range of −45 deg. to +45 deg. using virtual wind tunnel simulators based on the Computational Fluid Dynamics (CFD) approach. Furthermore, the study deals with a linear modal analysis of the loaded blade subjected to aerodynamic loads, dead weight and angular velocity of the rotor. By modeling the blade as a thick shell, composite shell and through solid spatial finite elements (FE), a comparison of the final results regarding the modal characteristics of the blade is discussed. The objective of this comparison is to develop better understanding of the blade performance and find the best ways for computer analysis regarding the complexity of the model, computer resources and accuracy of the results. The authors consider this analysis and the corresponding conclusions as a crucial perquisite for further geometrical optimization of the flap-wise rigidity of the blade aiming reduction of the strain energy and the noise. The results of the study indicate that different solutions are possible to implement in achieving almost equal flap-wise rigidity along the blade.