A dynamic stochastic forcing method as a wall-layer model for large-eddy simulation
نویسندگان
چکیده
Turbulence-resolving simulations of wall-bounded flows at high Reynolds numbers are presently unattainable due to the need to resolve fully the energy-carrying eddies in the near-wall region. Hybrid Reynolds-averaged Navier–Stokes/large-eddy simulations (RANS/LES), in which the nearwall eddies are modelled in a Reynolds-averaged sense, provide a cost-saving alternative. However previous attempts at combining a RANS near-wall layer with a LES outer flow have resulted in a large transition region which causes a shift in the mean velocity profile and low values of the skin friction coefficient. The present work presents a dynamic stochastic forcing method, that, when coupled with the detached-eddy simulation methodology, significantly speeds up this transition resulting in more accurate predictions of the mean velocity profile as well as the velocity fluctuations. The method is shown to be equally effective in a periodic and in a spatially developing flow.
منابع مشابه
Large-eddy simulation of turbulent flow over an array of wall-mounted cubes submerged in an emulated atmospheric boundary-layer
Turbulent flow over an array of wall-mounted cubic obstacles has been numerically investigated using large-eddy simulation. The simulations have been performed using high-performance computations with local cluster systems. The array of cubes are fully submerged in a simulated deep rough-wall atmospheric boundary-layer with high turbulence intensity characteristics of environmental turbulent fl...
متن کاملNumerical Study of Reynolds Number Effects on Flow over a Wall-Mounted Cube in a Channel Using LES
Turbulent flow over wall-mounted cube in a channel was investigated numerically using Large Eddy Simulation. The Selective Structure Function model was used to determine eddy viscosity that appeared in the subgrid scale stress terms in momentum equations. Studies were carried out for the flows with Reynolds number ranging from 1000 to 40000. To evaluate the computational results, data was compa...
متن کاملMixed Large-Eddy Simulation Model for Turbulent Flows across Tube Bundles Using Parallel Coupled Multiblock NS Solver
In this study, turbulent flow around a tube bundle in non-orthogonal grid is simulated using the Large Eddy Simulation (LES) technique and parallelization of fully coupled Navier – Stokes (NS) equations. To model the small eddies, the Smagorinsky and a mixed model was used. This model represents the effect of dissipation and the grid-scale and subgrid-scale interactions. The fully coupled NS eq...
متن کاملMixed Large-Eddy Simulation Model for Turbulent Flows across Tube Bundles Using Parallel Coupled Multiblock NS Solver
In this study, turbulent flow around a tube bundle in non-orthogonal grid is simulated using the Large Eddy Simulation (LES) technique and parallelization of fully coupled Navier – Stokes (NS) equations. To model the small eddies, the Smagorinsky and a mixed model was used. This model represents the effect of dissipation and the grid-scale and subgrid-scale interactions. The fully coupled NS eq...
متن کاملBlood Flow Simulation in an Aorta with a mild coarctation Using Magnetic Resonance Angiography and Finite Volume Method
Coarctation of the aorta is one of the five main congenital cardiovascular failures, accounting for 6–8 percent of these failures. This research aimed to simulate the blood flow of a seventeen-year-old male teen with a mild coarctation at one-third of his aorta's descending branch. The simulation was performed by extracting the domain and the input pulsatile velocity signal as the boundary cond...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2006