Vibrations of wind turbine blades in standstill: Mapping the influence of the inflow angles

S. G. Horcas*, N. N. Sørensen, F. Zahle, G. R. Pirrung, T. Barlas

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

817 Downloads (Pure)

Abstract

The present investigation used numerical simulations to study the vibrations of a wind turbine blade in standstill. Such vibrations are presumed to affect horizontal axis wind turbine designs and can jeopardize the structural integrity of the machine. The applied numerical methods relied on a fluid–structure interaction (FSI) approach, coupling a computational fluid dynamics (CFD) solver with a multibody finite-element structural solver. A 96-m-long wind turbine blade was studied for a large parametric space, accounting for the variation of both pitch and inclination. The inclination was defined as the angle between the freestream velocity and the cross-sectional plane at the root, allowing for the introduction of a flow component in the spanwise direction. The pitch variation corresponded to the rotation of the inflow around the spanwise axis, steering the angles of attack seen by the airfoils. Two regimes of vibrations were characterized, depending on the considered range of the inclination angle. For high inclinations, the pitch angles leading to vibrations clustered around a particular region of the parametric space, and the appearance of large oscillations was accompanied by the synchronization of the loading with the frequency of motion. At low inclination angles, the mechanism triggering vibrations was relatively similar, even if the excitation spectrum was richer, and the critical pitch angles seemed to be more scattered. Regardless of the inflow, the problem was highly three-dimensional, and several complex flow phenomena such as oblique shedding and phase dislocations were identified.
Original languageEnglish
Article number054105
JournalPhysics of Fluids
Volume34
Issue number5
Number of pages28
ISSN1070-6631
DOIs
Publication statusPublished - 2022

Fingerprint

Dive into the research topics of 'Vibrations of wind turbine blades in standstill: Mapping the influence of the inflow angles'. Together they form a unique fingerprint.

Cite this