Design and CFD Analysis of Windmill Blade

Abstract

The power generation problem is one of the important aspects of the world that has to address with high level of scientific reasoning and profound knowledge in the field of energy sources. Power can also be obtained from renewable resources, which include hydro power plants, solar power plants, solar thermal power plants and most importantly wind turbines. Hence harnessing and exploiting the energy comprised in the wind is important. Development of horizontal axis wind turbines (HAWTs) for small-scale application is important. A six bladed wind turbine system using the airfoils- Gottingen 364 and 682 were taken for the research. Using the design knowledge of on airfoils, key factors lift, drag and stall of the airfoil were studied and twist of the blade segments are designed with precision. Hence, the blades for a six bladed wind turbine system is designed for the optimal coefficient of lift value using Q-blade software with careful consideration at each location. Further, the aerodynamic parameters i.e. drag force, lift force, coefficient of drag, coefficient of lift and lift to drag ratio., pertaining to the wind turbine, the necessary calculations are formulated with the aid of Computational Fluid dynamics (CFD). Using the appropriate procedure of K-ϵ method to solve for the wind flow over the blade in an enclosed medium, the output parameters are calculated from the flow pattern in two functional form. By this method it is possible to reach the maximum amount of accuracy in carrying out the analysis and one can also obtain a very detailed output results. To check the aerodynamic design performance, the six bladed wind turbine system is validated using Numerical Study Computational Fluid Dynamics (CFD) using standard software’s (ANSYS-FLUENT) which forecast the performance of blades at low wind velocities. The parameters which are taken for analysis are carefully checked and correlated with IEC- 61400 Standard of small wind turbine system. The average wind velocity at hub height 3m/s is taken as wind designed input and the proposed designed six bladed wind turbine for each airfoils is carried for analysis. A six bladed wind turbine system having Gottingen airfoils 364,384,428,480 and 682 respectively were studied.