This award will support collaborative research between Dr. Mark Glauser, Clarkson University and two French scientists: Dr. Jean-Paul Bonnet and Dr. Joel Delville, both from the Laboratory for Aerodynamic Studies, University of Poitiers, France. The object of the project is to investigate the role that coherent structures play in practical turbulent flows, a topic of great interest and importance to the aerospace industry. The investigators will examine coherent structures in five different shear layers, using all or part of the following techniques: pseudo-flow visualization, proper orthagonal decomposition (POD) and dynamical systems theory. The five flows are: the plane mixing layer, the lobed mixer (a device used to generate streamwise vorticity), the axisymmetric jet mixing layer, the separated flow in an axisymmetric sudden expansion, and a supersonic wake. The French research group will provide a significant contribution to this effort, since they have studied the plane shear layer extensively and are knowledgeable in the application of the pseudo flow visualization technique. In addition, the University of Poitiers has unique facilities for the study of supersonic flow .