Calculation of Flow over Multielement Airfoils at High Lift

An interactive boundary-layer procedure has been used to calculate the flow around three two-element airfoil arrangements. The procedure is known to be accurate, is seen as the foundation of a generally applicable calculation method, and is used here in comparatively simple form. The calculated results are in close agreement with measurements for angles of attack up to around 10 deg, with flap-deflection angles of up to 20 deg. The range of accuracy of the predictions can be extended by the incorporation of the wake, and this will be required to deal with high angles of attack, high flap deflection angles, and airfoil elements with smaller slot gaps than those considered here.