Accurate and reliable CFD simulation of temperature stratification in indoor environment is needed for the design and evaluation of displacement ventilation in buildings. This paper presents a detailed and systematic evaluation of the capability of 3D steady RANS CFD simulations to predict the temperature stratification in a room. The evaluation is based on sensitivity analysis and validation w...

Validation simulations are presented for turbulent flow in a staggered tube bank, geometry similar to the lower plenum of a gas-cooled high temperature reactor. Steady 2D RANS results are compared to unsteady 2D RANS results and experiment. The unsteady calculations account for the fact that nonturbulent fluctuations (due to vortex-shedding) are present in the flow. The unsteady computations ar...

The majority of industrial computational fluid dynamics simulations are steady. Such simulations therefore require numerical methods which can rapidly converge a boundary value problem, typically either the Euler or Reynolds-averaged Navier–Stokes (RANS) equations. In this chapter we outline two major approaches: time-marching methods built on top of Runge–Kutta time-stepping schemes and Newton...

Large Eddy Simulation (LES) and Reynoldsaveraged Navier-Stokes (RANS) calculations have been used to predict the development, separation, reattachment and downstream recovery of the flow over a smoothly contoured ramp. The statistically two-dimensional upstream flow separates along the ramp surface and then reattaches downstream on a flat section. A canonical flatplate turbulent boundary layer ...

Xiao and Jenny (2012) proposed an interesting hybrid LES/RANS method in which they use two solvers solve the RANS LES equations entire computational domain. In present work this is simplified used as a RANS-LES method, wall-modeled LES. The are employed Near walls, flow governed by steady solver; drift terms added to DES ensure that time-averaged fields agree with field. Away from region, field...

Computational fluid dynamics using the Reynolds-averaged Navier–Stokes (RANS) remains most cost-effective approach to study wake flows and power losses in wind farms. The underlying assumptions associated with turbulence closures are biggest sources of errors uncertainties model predictions. This work aims quantify model-form RANS simulations farms at high Reynolds numbers under neutrally strat...

In this work, a new numerical model for cross-shore beach profile evolution, IH2VOF-SED, is developed. It consists in the bidirectional coupling of 2D RANS hydrodynamic solver and sediment transport module. The resulting extensively validated against three benchmark cases at different scales, attending to hydrodynamics, bottom shear stress bathymetry evolution. Comparisons between experimental ...

Numerical simulations based on a high-order discontinuous Galerkin solver were performed to investigate two-dimensional flapping foils at moderate Reynolds numbers, moving with different prescribed harmonic motion laws. A Spalart–Allmaras RANS model and without an algebraic local transition modification was employed for the resolution of multiple kinematic configurations, considering both moder...

We present results with a parallel CFD code that computes steady-state solutions of the Reynolds-Favre averaged Navier-Stokes equations for the simulation of the turbulent motion of compressible and incompressible Newtonian fluids. We report on preliminary experiments on 2D and 3D problems, for both internal and external flow configurations. In this communication we present numerical results wi...