INFLUENCE OF FIXED PITCH ANGLE ON THE PERFORMANCE OF SMALL SCALE H-DARRIEUS

摘要

The performance of a Vertical Axis Wind Turbine (VAWT) is numerically analyzed. Influence of fixed pitch angle is studied to get tendencies on the characteristic curves. The set up corresponds with an H-Darrieus with three straight NACA airfoils attached to a vertical shaft. Two-dimensional, transient, Navier Stokes equations are solved with a Third-Order Muscl scheme using SIMPLE to couple pressure and velocity. At least three revolutions must be simulated to get the periodic behaviour. Transition SST turbulence model has been chosen based on literature. Pitch angles of -6° and -10° have been analyzed with Tip Speed Ratios ranging from 0.7 and 1.6. The pitch angle of -10° improves the performance of the wind turbine. Instantaneous and averaged power coefficients as well as detailed flow field around the airfoils are shown.