The Representation of Planar Separated Flow by Regions of Uniform Vorticity

After some introductory remarks about the role of inviscid models in the representation of separated flow in two and three dimensions, an examination is made of the local behaviour of an inviscid model of planar separated flow. It is supposed that a body, together with a closed wake, is surrounded by an irrotational stream of an incompressible fluid. The wake is composed of one or more recirculating regions, in each of which the total pressure and the vorticity are uniform. Vortex sheets bound the various regions. The behaviour of the flow in the corners and cusps which form between the vortex sheets and the body, and the matching of the flows in adjacent regions, lead to some conclusions about possible inviscid flow structures. It is both a pleasure and an honour to be here in Göttingen, one of the main sources of inspiration and progress in fluid mechanics, to celebrate the 75th anniversary of the founding of the Aerodynamische Versuchsanstalt. It is a particular privilege to bring you greetings from the Royal Aircraft Establishment, another home of aeronautical research.