The Flow Past a Yawed Slender Delta Wing with Leading-Edge Separation

Abstract

The flow past a delta wing with low aspect ratio at incidence separates from its leading edge. This separation due to fluid viscosity greatly affects the wing performance. In the present paper, the flow over a yawed slender delta wing with leading edge separation is considered. The flow field is approximated by the potential flow model presented by C.E. BROWN and W.H. MICHAEL, Jr., in which each spiral vortex is represented by a line vortex with its strength linearly increasing and also a feeding vortex sheet is added which supplies vorticity from each leading edge to a line vortex on a corresponding side.
The calculation is performed in the case of two parameters being small, that is, one of these is the incidence parameter K_α=α/tanδ, the other is the yaw one K_β=β/tanδ, where α is the incidence angle, β the yaw angle and δ the semi-apex angle of the wing, respectively. It is shown that the leading edge separation on the yawed delta wing leads to interesting wing characteristics and the present method will be very useful as the value of Kα is reduced.