Separated and unsteady flows in aeronautics: Research at the University of Bristol

Abstract

The aerodynamics of aeronautics to most people is prob-ably synonymous with the aerodynamics of streamlined shapes. By contrast aerodynamics outside of aeronautics may well conjure up a picture of a non-uniform airstream approaching a building, creating an unsteady, separated flow. That these pictures are misleading would be known to most of those connected with aeronautics—aircraft do develop separated, unsteady flows, and outside of aero-nautics there is interest in aerodynamic efficiency and smooth attached flows. Until comparatively recently, however, the need in aeronautics has been to increase aerodynamic efficiency, and virtually all major research topics seem to have been related to steady, smooth flows; the problems connected with separated and unsteady flows (e.g. wing stall, or buffeting in bomb bays) have, by contrast, usually been tackled on an ad hocbasis, without very much emphasis being given to understanding whythe flow was as it was.