We present an algorithm for compressible Large Eddy Simulation (LES) using unstructured tetrahe-dral grids. Two methods for simulation of the sub-grid scale stresses are examined. The rst method is the Monotone Integrated Large Eddy Simulation (MILES) technique of Boris, Oran and Grinstein, whereby the energy transfer from the resolved scales to the subgrid scales is modeled using the inherent ...

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...

_q}:anslation memories are t)ronfising devi('es for artt;omati(t ransla t ion. Thei r main weakuess, however, is poor coverage, on llllSeell {;ex|;. ]ill this t)at)er, l;he use of a hierarchical l;ranslat ion memory, (:onsisting of a ('as(:ade of finite si;~d;e t ransducers , is t)rot)os(;d. A mmfl)er of tr~nsdu(:e, rs is al)l)]ied to (;onverl; s(;ni;enee 1)airs fl:om a t)ilingual cortms into t...

Abstract: Detached-eddy simulation (DES) based on the v-f Reynolds-averaged Navier-Stokes (RANS) model is developed and tested. The v-f model incorporates the anisotropy of near-wall turbulence, which is absent in other RANS models commonly used in the DES community. The v-f RANS model is modi ed in order that the proposed v-f -based DES formulation reduces to a transport equation for the subgr...

Numerical simulations of complex large-scale flow systems must capture a variety of physical phenomena in order to predict the flow accurately. Currently, many flow solvers are specialized to simulate one part of a flow system effectively, but are either inadequate or too expensive to be applied to a generic problem. As an example, the flow through a gas turbine can be considered. In the compre...

At low Reynolds numbers, laminar-turbulent transition occurs on the suction side of high-lift low-pressure turbine blades. The prediction of this flow is an important step in low-pressure turbine design. Thus the laminar-turbulent transition must be modeled or resolved. The flow around the high-lift low-pressure turbine blade T106C is predicted using RANS simulations, without and with transitio...

Both RaNS (Reynolds-averaged Navier-Stokes) and DES (Detached Eddy Simulation) type turbulence models were used in conjunction with a two-fluid model of bubbly flow and a new subgrid air entrainment model to predict air entrainment and transport in a hydraulic jump. It was found that the void fraction profiles predicted by both methods are in agreement with the experimental data in the lower sh...

This paper investigates the influence of the propeller on the drag of twin self-propelled AUVs, firstly, to examine the fleet performance for various propulsive conditions of leading and following AUV and, secondly, to study the parametric influence of transverse separations and longitudinal offsets on the fleet’s drag. A series of CFD RANS-SST simulations have been performed at the Reynolds Nu...

In this paper, a gas kinetic solver is developed for the Reynolds Average Navier-Stokes (RANS) equations in two-space dimensions. To our best knowledge, this is the first attempt to extend the application of the BGK (Bhatnagaar-Gross-Krook) scheme to solve RANS equations with a turbulence model using finite difference method. The convection flux terms which appear on the left hand side of the R...