Studying and analysis of deformation and stresses in horizontal-axis wind turbine using fluid-structure interaction method

Abstract

Fluid-structure interaction (FSI) studies have become an important tool in the development of wind turbine blades as well as for analyzing and optimizing Horizontal Axis Wind Turbine (HAWT). The most essential elements for estimating the turbine blade strength to withstand extreme wind loads and aerodynamic performance are the blade deformation and the associated stresses. This study aims to compare the strength and analyze the deformation behavior of two models of HAWT blades. A three-dimensional model was created and loaded into a Finite Element (FE) model for analysis. The Computational Fluid Dynamics (CFD) investigation was coupled with the structural model using one-way FSI. In this article, the effect of the aerodynamics on the blade surface of a small HAWT has been studied numerically and experimentally. The airfoil used for the blade profile is S826 airfoil. To provide an appropriate displacement for static measurements, the blade in the experimental investigation is made of thermoplastic polyurethane material (TPU). It is noted that the current experimental findings verify the simulation results, and a comparison between the simulations and the experimental findings reveals a reasonable agreement. The numerical simulations are also implemented on a HAWT epoxy E-glass unidirectional (EEGUD) material. It can be concluded from this study that the blade deformation and stress on the blades are related to the wind speed. The deformation along the span length exhibits nonlinear variation that gradually increases from the blade root and reaches its maximum at the blade tip position. The tip deflection and equivalent stress were found to increase with an increase in wind speed. The dynamic analysis at different tip speed ratios shows the highest deformation at λ = 4, for wind speed of 20 m/s.