Published online by Cambridge University Press: 04 July 2016
This paper proposes a correlation which attempts to relate an aerofoil's low speed dynamic stall onset incidence to particular parameters describing its stall behaviour in steady conditions. These parameters, which can be derived from experiment or predictive algorithm, are the incidence of steady stall and a term related to trailing-edge separation characteristics. The correlation is based on a large amount of data obtained from a number of aerofoils broadly classified into two families: the NACA four digit series of symmetrical sections and a family of four profiles with the NACA 23012 as the generic shape.
The correlation has been extended to low pitch rates outside the “deep” dynamic stall range and, whilst it pertains to stalling under ramp motions, a link has been established with oscillatory motions. The potential of the correlation is demonstrated by its application to the design of a symmetric aerofoil for use on wind turbines.
Currently with Westland Helicopters, Yeovil, Somerset
Currently Lecturer, The University of Paisley, Scotland