Author: B. E. Launder

Publisher:

Published: 1980

Total Pages: 0

ISBN-13:

In 1904 Prandtl published the boundary layer equations and, thereby, firmly stamped the direction of research in fluid mechanics for the next sixty-five years. In Aerodynamics especially (a discipline that is intrinsically concerned with non -recirculating flows) the decomposition of the flow into an inviscid region bounded, near rigid surfaces, by thin viscous zones, proved such a powerful stimulus that it sustained decades of outstandingly successful theoretical and experimental work. Yet, in contrast, only a relatively small proportion of the flows in and around Mechanical Engineering equipment are reasonably well described by the thin shear flow equations. Commonly flow recirculations are present, particularly in heat transfer equipment where a judiciously provoked separation is often found to raise substantially the level of heat transfer coefficient. Because the equations describing such flow phenomena are much more difficult to solve than the boundary layer equations, the contributions made by computational fluid mechanics to the design of Mechanical Engineering equipment has been correspondingly less than in Aeronautics. By 1970 the predominance of thin shear flow studies had begun to weaken and the ensuing decade has seen a steady development of computational procedures for recirculating flow and the essential supporting experimental techniques. Although considerable progress has been made, however, it is clear that we are still nearer the beginning than the end in providing the necessary fundamental research basis in this area. Accordingly, to provide both a forum for airing current work and a springboard for further research, the K-8 Committee of the Heat Transfer Division decided to sponsor a session at the 1980 WAM on Momentum and Heat Transfer in Recirculating Flows. In fact, the response to the announcement of the session was so vigorous that two sessions have been scheduled at which the twelve papers contained in the present volume are to be presented. The papers span many of the current areas of work including: both computational and experimental studies; laminar and turbulent flows; and both steady and unsteady flow phenomena.