Aerodynamic coupling of rotor and tower in HAWTs

authored by: Alejandro Gomez, Joerg R. Seume
Abstract: This article presents results obtained computationally for the influence of the tower on the aerodynamics of the rotor. Tower models implemented in aeroelastic codes fail to account for aerodynamic: coupling of the rotor and the tower. Computational studies of this coupling have shown that induced unsteady circulations both on the blades and on the tower appear during the blade passage which cannot be? accounted for using a traditional BEM analysis integrated with a Beddoes-Leishman dynamic: stall model. On the blades, the effect can be represented by means of an induced aerodynamic force which is a function of the circumferential position and geometrical parameters. The flow around the tower is affected in such a way that the upwind stagnation point and the vortex separation points of its wake are displaced 3 times per revolution, for a three bladed rotor. This induces unsteady lateral loads on the tower and also a meandering of the wake. An interaction of the profile aerodynamic characteristics with the unsteady vortex shedding of the tower is observed. The methodology used is based on 2D CFD simulations whose results are generalized for an efficient implementation on aeroelastic codes based on BEM formulations. The1 results are summarized in a correction function for the lift coefficient of the airfoil to account for the aerodynamic: coupling with the tower. The work presented in this paper represents an important step towards the understanding of the effects of the 3p loads on the support structure of a HAWT due? to rotor-structure aerodynamic and aeroelastic interaction.
Organisation(s): Institute of Turbomachinery and Fluid Dynamics
Type: Conference contribution
Pages: 4304-4314
No. of pages: 11
Publication date: 2009
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Energy Engineering and Power Technology, Renewable Energy, Sustainability and the Environment
Sustainable Development Goals: SDG 7 - Affordable and Clean Energy