Dynamic analysis of a wind turbine blade

Abstract

The world is running out of conventional energy sources and there is a pressing need of utilizing non-traditional energy sources to endure the ever escalating energy needs. Wind turbines provide an alternative way of generating energy from the power of wind. At windy places, wind speeds can achieve scintillating values of 10-12 m/s. Such high speeds of wind can be utilized to harness energy by installing a wind turbine usually having 3 blades. The geometry of the blades is made as such that it generates lift from the wind and thus rotates. The lift force generates a moment around the hub and thus the combined torque effort of 3 blades rotates the turbine and generates electricity. Rotational speed of the blades is usually 6 times that of wind speed. In this project, validation of a beam (a geometrical approximation of a blade) in vibration analysis is taken up first. The natural frequencies are matched with a published research paper and then an actual blade geometry is taken up to validate its 1st 3 natural frequencies with a published research paper and then a CFD analysis is taken up to find the lift and drag forces on the blade and subsequently these forces are used to calculate the fatigue life of the blade. Suitable materials for different parts of the blade are taken to see which combination of materials gives better results.