Aerodynamic Forces on Finite Wings in Oscillatory Flow: An Experimental Study

This report describes aerodynamic lift and pitching moment measurements on finite wings in oscillating vertical gusts of varying frequency parameter and gust amplitude. A set of six conventional wings with varying aspect ratio, sweep angle, and taper are tested. The results show that the variation of aerodynamic force per unit gust amplitude with frequency parameter is independent of freestream velocity, wing incidence, and gust amplitude but is considerably influenced by wing sweep. These experimental results are compared with a lifting surface theory for two of the test planforms and show good agreement. The effect on the aerodynamic forces of allowing free transition on the wing surfaces is also investigated.