Design of a Small Horizontal Axis Wind Turbine

摘要

Wind turbine rotor is the most significant part of a wind turbine. The design of wind turbine rotor blades can be achieved by many methods. The blade element momentum theory (BEMT) is one such method. Despite its simplicity, the BEMT gives quite accurate results. In the current work, wind turbine blades for small horizontal axis wind turbine were designed using Schmitz formulas for optimum rotor theory in conjunction with BEMT. The current design used the SG6043 airfoil. A low wind speed of 6 m/s is set for the design. The blade is divided into a number of equal length elements. MATLAB code iterates the solution to calculate the chord length and twist angle for each blade element until convergence. In each iteration, the angle of attack, as well as the lift and drag coefficients, are interpolated from airfoil data files at maximum glide ratio (Lift-to-Drag ratio). Blade element momentum theory is used to characterize the performance of the designed rotor. Wilson-Walker method for the correction of Thrust coefficient and axial induction factor is used in the calculation. Typical power coefficient vs. tip-speed ratio is reported with a maximum power coefficient of 0.53 is at a tip-speed ratio of around 6.