2-DIMENSIONAL VISCOUS-FLOW PAST FLEXIBLE SAIL SECTIONS CLOSE TO IDEALINCIDENCE

A model of the viscous flow past a flexible sail section operating nea r the ideal incidence is described. Viscous effects are calculated via weak viscous-inviscid interaction of a panel method and an integral b oundary layer method, and a new model for the leading edge separation bubble is introduced. The flexible section is allowed to deform in res ponse to the pressure and shear stresses acting on it. Results are pre sented for the effect of incidence, excess length and Reynolds number on the development of the boundary layers on each side of the section and the consequences for the lift and drag of the section are describe d. The numerical model is compared with experimental results, giving i n general good agreement and shedding light on the physics of the visc ous flow past flexible membranes.