Friday, October 4, 2013
Julian Cole Lecture in Aerospace
Progress and challenges in numerical simulation of multi-physics turbulent flows in complex geometry
Parviz Moin, Franklin P. and Caroline M. Johnson Professor in the School of Engineering, Mechanical Engineering - Flow Physics and Computation, Stanford University
A review of modern large eddy simulation (LES) for numerical simulation of multi-physics turbulent flows will be presented. Simulations of practical engineering configurations require the ability to handle complex geometries. Extension of LES methodology to unstructured grids through the use of differential filters will be described. A novel adaptation technique is suggested where the mesh (and/or filter) is refined in regions of the flow where estimates of the subgrid scale energy is largest. Applications range from prediction of supersonic jet noise, stalled 3D diffuser, combustion in realistic gas turbine engines and separation control on airfoils. It is demonstrated that in boundary layers the dynamic subgrid scale modeling procedure predicts the location of transition from laminar to turbulent flow irrespective of the path to transition. Development of wall models for LES of high Reynolds number boundary layers, and subgrid scale models for muti-physics phenomena where the dynamics of thin interfaces are critical to the development of large scale flow remains a pacing item for LES. Future outlook for computer architectures and routine use of LES in industrial settings will be discussed.