Comparison of Experimental results with CFD for NREL Phase VI Rotor with Tip Plate

Year 2012, Volume: 2 Issue: 4, 556 - 563, 01.12.2012

Eswararao Vsj Anjuri

Abstract

This article presents the results of 3D CFD rotor computations of a NREL Phase VI rotor with tip plate, a stall-regulated turbine with full-span pitch control, has a power rating of 20 kW. In this paper, A full three dimensional CFD–RANS approach by modeling the whole rotor of a wind turbine by means of periodicity was used. All the simulations were performed using the commercial multi-purpose CFD solver ANSYS CFX 12.1 with the transition model of Langtry and Menter is applied to a rotor at stationary wind conditions without wind shear. The comparisons were done for the blade with 0° yaw angle and 3° tip pitch angle on a single rotor blade without tower and nacelle. Reasonably good agreement is obtained when comparing modeled mechanical effects like power and thrust with findings from measurements. Similarly the spanwise force distributions are compared with experimental results for two wind speeds along with pressure distributions at five different spanwise locations. It is shown capability of 3D CFD computations that can be used to extract information about three-dimensional aerodynamic effects.

Keywords

Navier–Stokes; Computational fluid dynamics; Wind turbine aerodynamics; NREL Phase VI Rotor; Tip Plate

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• P = Rotor Mechanical Power (W) T = Rotor Torque (N-m) CN = Normal force coefŞcient Ω = Angular Velocity (rad/s) Cp = Pressure coefŞcient r = Radial position from hub (m) R = Rotor radius (m) x = Chordwise position (m) c = Rotor chord (m) ρ = Density (kg/m^3) v = Wind velocity (m/s) ω = RPM y+ = Non-dimensional distance of the Şrst grid point off the blade surface