UNSTEADY AERODYNAMIC GUST RESPONSE INCLUDING STEADY FLOW SEPARATION

A series of experiments are performed to investigate and quantify the unsteady aerodynamic response of an airfoil to a high reduced frequency gust including the effects of the gust forcing function waveform, airfoil loading, and steady flow separation. This is accomplished by using an axial flow research compressor to experimentally model the high reduced frequency gust forcing function and replacing the last stage stator row with isolated instrumented airfoils. Appropriate data are correlated with predictions from flat plate and cambered airfoil convected gust models. The airfoil surface steady loading is shown to have a large effect on the unsteady aerodynamic response. Also, the steady flow separation has a significant influence on the gust response, particularly upstream of the separation point and in the airfoil trailing-edge region. © 1990 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.