Experimental and numerical study of radial flow and its contribution to wake development of a HAWT

Abstract

The scope of this work was to investigate radial flow

component for a Horizontal Axis Wind Turbine in ax- ial flow conditions and to assess its impact on the

turbine operation. This was done by means of Parti- cle Image Velocimetry and numerical simulation with

a 3D unsteady potential-flow panel model. A direct

comparison between the numerical and experimen- tal radial velocity results show differences in the tip

and root regions. These differences have important

implications on the wake development just at the

moment of release of the tip vortex. Moreover, the

impact of the radial velocities on the blade loading

has been studied using the numerical results. The

contribution of the radial velocity to the normal load

on the blade is only slightly appreciable in the tip and

root regions of the blade. However, as the numerical

model does not account for viscous effects, further

analysis of impact on boundary layer development is

necessary.