Iutam Symposium on the Physics of Wall-Bounded Turbulent Flows on Rough Walls

The study of wall-bounded turbulent flows is of considerable interest from both scientific and practical view points. As such it has attracted a great deal of research over the last 100 years. Much research has concentrated on flows over smooth walls since these are simpler from experimental, numerical and theoretical standpoints. The flow over rough walls has still received considerable attention but progress has necessarily been slower. Perhaps the most essential problem (certainly from a practical point of view) is to be able to predict the skin-friction drag acting on a plate (or a body) given a certain known roughness characteristic of the surface. Unfortunately this has proved to be very difficult since even the simplest rough surfaces can be characterised by a number of different parameters and we still cannot directly connect these to the fluid dynamic drag in a given situation. Various theories and models have been proposed in order to make progress but there is still some disagreement in the community as to the correct understanding of these important flows. The IUTAM Symposium on the Physics of Wall-bounded Flows on Rough Walls was held in Clare College, Cambridge from the 7th - 9th July 2009 in order to bring together various expert researchers in the field to try and resolve some of these disagreements and to develop a consensus on the most fruitful directions of future research.