An eighth-order filter method for a wide range of compressible flow speeds (H.C. Yee and B. Sjogreen, Proceedings of ICOSAHOM09, June 22-26, 2009, Trondheim, Norway) are employed for large eddy simulations (LES) of temporally evolving mixing layers (TML) for different convective Mach numbers (M c ) and Reynolds numbers. The high order filter method is designed for accurate and efficient simulations of shock-free compressible turbulence, turbulence with shocklets and turbulence with strong shocks with minimum tuning of scheme parameters. The value of M c considered is for the TML range from the quasi-incompressible regime to the highly compressible supersonic regime. The three main characteristics of compressible TML (the self similarity property, compressibility effects and the presence of large-scale structure with shocklets for high M c ) are considered for the LES study. The LES results using the same scheme parameters for all studied cases agree well with experimental results of , and published direct numerical simulations (DNS) work of Rogers & Moser (1994) and Pantano & Sarkar (2002).
Key words: DNS, LES, Homogeneous turbulence, Mixing layer, SWBLI
Motivation and ObjectiveFor the last decade there has been an increase in the use of computational fluid dynamics (CFD) in engineering science, not only for fundamental understanding of complex compressible turbulent physics, but also for the development and design of industrial devices. Owing to the recent progress in petascale computing, in tandem with advances in algorithm development for accurate direct numerical simulations (DNS) and large eddy simulations (LES) of shock free compressible turbulence and turbulence with strong shocks, this type of DNS and LES computation has gradually been able to tackle more complex flows physics. Advances in flow visualization tools have paved the way to extracting valuable information from the computed results containing hundreds of terabytes of data. Examples include * This work was performed while the first author was a visiting scholar at the Center for Turbulence Research, Stanford University.