The paper presents a comparison of several hybridization between RANS and LES, and their potential and limitations in an industrial context. The first part of the paper addresses an often eluded problem in the hybrid RANS/LES community: the importance of the baseline statistical model. A new robust low-Reynolds number eddy-viscosity model, derived from a Reynolds-stress model and accounting for...

A Large-Eddy Simulation of several cycles of a spark-ignition engine with port fuel injection has been performed. The investigated engine is a modified Rotax-engine with one cylinder and four valves, built and measured (Heidenreich, Private communication) by the Institute of Reciprocating Engines of the University of Karlsruhe (IFKM). A recently modified (Magagnato et al., 2008) progress variab...

Formulation, implementation and applications of a numerical algorithm to simulate turbulent, incompressible, isothermal flows are the main objectives of this work. The transient three-dimensional flow is analyzed using an explicit Taylor-Galerkin scheme and the finite element method with hexahedrical eight-node element. The scheme adopted for turbulence treatment is Large Eddy Simulation. For s...

Oil droplet transport under a non-breaking deep water wave field is investigated herein using Computational Fluid dynamics (CFD). The Reynolds-averaged Navier–Stokes (RANS) equations were solved to simulate regular waves in the absence of wind stress, and the resulting water velocities agreed with Stokes theory for waves. The RANS velocity field was then used to predict the transport of buoyant...

Large Eddy Simulation (LES) is performed to study the physiological pulsatile transition-to-turbulent non-Newtonian blood flow through a 3D model of arterial stenosis by using five different blood viscosity models: (i) Power-law, (ii) Carreau, (iii) Quemada, (iv) Cross and (v) modified-Casson. The computational domain has been chosen is a simple channel with a biological type stenosis formed ec...

Communicated by D.B. Spalding) A model equation for the scalar dissipation rate, based on the Two Scale Direct Interaction Approximation (TSDIA) of Yoshizawa [1J was solved and applied to a turbulent round jet in conjunction with turbulence modelling based on the eddy viscosity and diffusivity. The model coefficients were adjusted by using a similarity analysis for the round jet. This led to an...

The linear decomposition of the circulation across a tidal front suggested by an analytical model (Dong et al. 2004) is examined using a two-dimensional numerical model. Three basic experiments are performed for a homogenous ocean, and winter and summer fronts, respectively, in which the cross-frontal circulation can be interpreted within the context of the analytical solution. Through a series...

A generic shortcoming of constant-depth (or “z-coordinate”) ocean models such as MOM5 and Nucleus for European Models the Ocean (NEMO) is a tendency advection scheme to produce unphysical numerical diapycnal mixing, which may exceed explicitly parameterized mixing based on observed physical processes. Megann (2018, https://doi.org/10.1016/j.ocemod.2017.11.001) estimated effective diffusivity in...