Large-Eddy Simulation of Laminar-Turbulent Breakdown at High Speeds with Dynamic Subgrid-Scale Modeling

Large-Eddy Simulation of Laminar-Turbulent Breakdown at High Speeds with Dynamic Subgrid-Scale Modeling
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
Total Pages: 60
Release: 2018-07-08
Genre:
ISBN: 9781722611972

The laminar-turbulent breakdown of a boundary-layer flow along a hollow cylinder at Mach 4.5 is investigated with large-eddy simulation. The subgrid scales are modeled dynamically, where the model coefficients are determined from the local resolved field. The behavior of the dynamic-model coefficients is investigated through both an a priori test with direct numerical simulation data for the same case and a complete large-eddy simulation. Both formulations proposed by Germano et al. and Lilly are used for the determination of unique coefficients for the dynamic model and their results are compared and assessed. The behavior and the energy cascade of the subgrid-scale field structure are investigated at various stages of the transition process. The investigations are able to duplicate a high-speed transition phenomenon observed in experiments and explained only recently by the direct numerical simulations of Pruett and Zang, which is the appearance of 'rope-like' waves. The nonlinear evolution and breakdown of the laminar boundary layer and the structure of the flow field during the transition process were also investigated. El-Hady, Nabil M. Unspecified Center...

Large-Eddy Simulations of Turbulence

Large-Eddy Simulations of Turbulence
Author: M. Lesieur
Publisher: Cambridge University Press
Total Pages: 240
Release: 2005-08-22
Genre: Mathematics
ISBN: 9780521781244

Large-Eddy Simulations of Turbulence is a reference for LES, direct numerical simulation and Reynolds-averaged Navier-Stokes simulation.

Computational Fluid Dynamics

Computational Fluid Dynamics
Author: T. J. Chung
Publisher: Cambridge University Press
Total Pages: 1040
Release: 2002-02-07
Genre: Juvenile Nonfiction
ISBN: 9780521594165

Increasingly, computational fluid dynamics (CFD) techniques are being used to study and solve complex fluid flow and heat transfer problems. This comprehensive book ranges from elementary concepts for the beginner to state-of-the-art CFD for the practitioner. It begins with CFD preliminaries, in which the basic principles of finite difference (FD), finite element (FE), and finite volume (FV) methods are discussed and illustrated through examples, with step-by-step hand calculations. Then, FD and FE methods respectively are covered, including both historical developments and recent contributions. The next section is devoted to structured and unstructured grids, adaptive methods, computing techniques, and parallel processing. Finally, the author describes a variety of practical applications to problems in turbulence, reacting flows and combustion, acoustics, combined mode radiative heat transfer, multiphase flows, electromagnetic fields, and relativistic astrophysical flows. Students and practitioners - particularly in mechanical, aerospace, chemical, and civil engineering - will use this authoritative text to learn about and apply numerical techniques to the solution of fluid dynamics problems.