On the S809 airfoil's unsteady aerodynamic characteristics
Article first published online: 15 APR 2009
Copyright © 2009 John Wiley & Sons, Ltd.
Volume 12, Issue 8, pages 752–767, November 2009
How to Cite
Sheng, W., Galbraith, R. A. McD. and Coton, F. N. (2009), On the S809 airfoil's unsteady aerodynamic characteristics. Wind Energ., 12: 752–767. doi: 10.1002/we.331
- Issue published online: 16 NOV 2009
- Article first published online: 15 APR 2009
- Manuscript Accepted: 6 MAR 2009
- Manuscript Revised: 5 MAR 2009
- Manuscript Received: 14 NOV 2007
- Engineering and Physical Sciences Research Council, in collaboration with Garrad Hassan Ltd. and the National Renewable Energy Laboratory's National Wind Turbine Centre, Boulder, CO, USA. Grant Number: GR/S42446/01
- unsteady airfoil test;
- dynamic stall;
- stall onset;
- re-attachment modelling
The S809 airfoil dynamic characteristics, which are based on the airfoil dynamic tests at the University of Glasgow, are presented in this paper. The airfoil tests include static, ramp-type (ramp-up and ramp-down) and oscillatory motions at Reynolds numbers of 1.0 × 106 and 1.5 × 106 with and without the sand-tripped leading edge. This study aimed to explore the unsteady aerodynamic features of the S809 airfoil, such as the progression of separation from leading edge to trailing edge, the large trailing edge separation before stalling, the stall onset inception and the re-attachment convection, and to provide some useful data for tuning/refining the semi-empirical dynamic stall (DS) models, such as the Leishman–Beddoes DS model or its variations.
Experimental results show that the S809 airfoil has a complicated DS process that renders this airfoil a challenge for any modeller of the unsteady airloads. The leading-edge roughness has small effect on the static features, but significantly invokes earlier stall onset inception under dynamic conditions, while has small influence on the convective phase of the re-establishment of fully attached flow. Copyright © 2009 John Wiley & Sons, Ltd.