Low reynolds number airfoil for a wind turbine blade and method thereof

Abstract

A low Reynolds number airfoil for a wind turbine blade, the airfoil having a leading edgea trailing edge spaced from the leading edgea chorddefined as a straight line joining the leading edgeand the trailing edge, a chordlength defined as distance between the trailing edge and the point on the leading edgewhere the chordintersects the leading edgewherein the airfoil comprises a camberbetween 5% to 7% of the chordlength, the camberis disposed within a distance of 17% of the chordlength from the leading edgeand a thickness of the airfoil not greater than 7% of the chordlength. In an embodiment, it discloses A method of designing blade for low wind speed turbine for a site location, the method comprising obtaining time series data for the site location, computing a Weibull shape factor (K) and scale factor (C)corresponding to a Weibull distribution function based on the time series data for the site location, using K and C to identify energy intensive wind speed at the site location, determining blade length based on the energy intensive wind speed, K, C, a design power (PD) of the turbine, a design power coefficient (Cpd), and a density of the air (Ro), wherein the rated power of the turbine depends on load to be connected of the turbine, selecting a generator for use with the turbine, computing a design tip speed ratio based on a rated speed of the generator (NGD), a gear ratio (GR), the design power (PD), K, and C, identifying number of blades (B) depending on the design tip speed ratio and an end-use of the power being produced by the turbine; and identifying a chordlength and twist of the blade from root-to-tip.