Abstract
In order to clarify the aerodynamic characteristics of a ski-jumper in the forward-leaning position, wind-tunnel measurements are made of the lift and drag forces acting on a scaled-model human body, and the flow around the model is observed by using tufts, at various angles of incidence. Effects of the surface roughness are also examined to find that small roughness can increase the lift as well as the drag without essentially changing the lift-to-drag ratio, and thus can improve the aerodynamic characteristics. Various interesting features of the characteristics including the roughness effect are discussed in terms of the flow structures observed.
