Aerodynamic performance analysis of horizontal axis wind turbines

Abstract

The present work studies the wind energy resources in Egypt and the aerodynamic performance of propeller type and multi-bladed horizontal axis wind turbines with three different airfoil blade sections (flat-plate, symmetric and circular-arc airfoils). Power, thrust and torque coefficients were investigated as functions of wind turbine design parameters (blade angle, rotor solidity, drag-to-lift coefficient ratio and blade section) and operating conditions (tip-speed ratios). Axial and tangential induction factors and drag coefficient were introduced in the calculations. Recommended design and operating values are given for each wind turbine. The analysis of the theoretical results shows that flat-plate and symmetric airfoil blade sections operate at a wider range of tip-speed ratios than that of circular-arc airfoil blade sections, so they are recommended for small and large sized wind turbines, respectively. Also, the analysis of the available local wind speed measurements indicates that the future potential of wind energy conversion systems in Egypt is promising. Several sites along the Mediterranean and Red Sea coasts have high annual average wind speed and power density of 6.4 m s −1 and 160 W m −2, respectively.