Dr. Andrew McMullan
Department of Engineering, University of Leicester
The plane mixing layer is a canonical flow type, often used in validation studies for Large Eddy Simulation and Direct Numerical Simulation research. Experimental evidence shows, however, that the mixing layer displays a hypersensitivity to its initial conditions, with the growth rate of the flow seemingly significantly affected by the initial conditions. In addition, the seminal work of Brown and Roshko (1974) discovered orderly coherent structures embedded within the turbulent flow. This seminar deals with the numerical simulation of plane turbulent mixing layers, and investigates the physics of the flow. The influence of computational parameters on the flow evolution will be considered. The topography of coherent structures in both the laminar and turbulent regions of the flow will be discussed, and the evolution of these structures will also be highlighted. A simple model which describes the growth of the turbulent coherent structures will be presented.