The present paper proposes a combination of the Baldwin Lomax and Smagorinsky turbulence models in order to compensate the de ciencies each one of these simple models exhibits. The proposed combination, named BLS, uses the turbulent viscosity of the Baldwin Lomax in the vicinity of walls, and a blend of Baldwin Lomax and Smagorinsky viscosity from the end of the inner layer (Baldwin Lomax) into...

A review of existing basic turbulence modeling approaches reveals the need for the development of unified turbulence models which can be used continuously as filter density function (FDF) or probability density function (PDF) methods, large eddy simulation (LES) or Reynolds-averaged Navier–Stokes (RANS) methods. It is then shown that such unified stochastic and deterministic turbulence models c...

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 attempt...

It is shown that a new mixed nonlinear/eddy viscosity LES model reproduces profiles better than a number of competing nonlinear and mixed models for plane channel flow. The objective is an LES method that produces a fully resolved turbulent boundary layer and could be applied to a variety of aerospace problems that are currently studied with RANS, RANS-LES, or DES methods that lack a true turbu...

This article presents a numerical study of turbulent flow around a generic three-dimensional prolate spheroid with a 20◦ angle of attack. The Reynolds number we use is a moderate one Re = 4 × 104. In this work we compare three different turbulence models : the RANS k − ε, the LES Smagorinsky and the VMS-LES. The numerical code makes use of a mixed FE/FV formulation based on tetrahedra. A Roe’s ...

Large-eddy simulation (LES) is commonly used in atmospheric simulations when the domain size is small enough to allow grid spacing that resolves turbulence. At these resolutions LES is more accurate than the Reynolds-averaged Navier-Stokes (RANS) models used for mesoscale simulations, but far less computationally intensive than direct numerical simulation (DNS). Grid nesting, used to transfer t...

The present paper concerns a numerical benchmark of various turbulence modelings, from RANS to LES, applied to Taylor-Couette-Poiseuille flows in a narrow gap cavity for six different combinations of rotational and axial Reynolds numbers. Two sets of refined Large-Eddy Simulation results, using the WALE and the Dynamic Smagorinsky subgrid scale models available within an in-house code based on ...

Large-eddy simulation (LES) is increasingly used as a tool for studying the dynamics of turbulence in engineering flows. In LES, one explicitly captures the dynamics of the large eddies while modeling the effects of the smaller eddies on the larger ones. Because the statistics of small scale turbulence are expected to be more universal than those of the large scales, LES offers the promise of w...