An Investigation of Re-Establishment of Fully Attached Aerofoil Flow from Stall in Unsteady Conditions. G.U. Aero Report 9431

Green, R.B. , Galbraith, R.A.M. and Coton, F.N. (1994) An Investigation of Re-Establishment of Fully Attached Aerofoil Flow from Stall in Unsteady Conditions. G.U. Aero Report 9431. Technical Report. Department of Aerospace Engineering, University of Glasgow.

Abstract

The following report summarises a three year research programme in the Department of Aerospace Engineering, University of Glasgow to investigate re-attachment over two-dimensional aerofoils performing pitching motion. The original motivation for the work was to understand how an aerofoil could generate negative lift coefficients at large positive angles of incidence (e.g. 10°) during so-called rampdown motions from high to low incidence. An extensive database of unsteady pressure measurements on thirteen aerofoils provided the basis for the analysis. This was supplemented by a number of specific tests, including an examination of the wind tunnel constraint effect using a high aspect ratio model. Additionally, a smoke flow visualisation facility was developed and used to examine particular aspects of the phenomenon identified in the pressure analysis. To complement the analytical work, a discrete vortex method and a semi-empirical dynamic stall model were applied to the ramp-down problem. The work resulted in a definitive physical description of the dominant mechanisms present in the ramp-down process. The work also validated the use of a universal time-delay within the Beddoes semi-empirical dynamic stall model to represent the variation of aerodynamic coefficients during ramp down.

• Item Type: Research Reports or Papers (Technical Report)
• Additional Information: Final contractor report for SERC/EPSRC, contract number GR/H16711.
• Status: Published
• Glasgow Author(s) Enlighten ID: Green, Dr Richard and Coton, Professor Frank and Galbraith, Professor Roderick
• Authors: Green, R.B., Galbraith, R.A.M., and Coton, F.N.
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Publisher: Department of Aerospace Engineering, University of Glasgow
• Copyright Holders: Copyright © 1994 Department of Aerospace Engineering, University of Glasgow
• Publisher Policy: Reproduced with the permission of the Department