An eddy-viscosity model for turbulent flows of Herschel–Bulkley fluids

A New Model for Prediction of Heat Eddy Diffusivity in Pipe Expansion Turbulent Flows

A new model to calculate heat eddy diffusivity in separating and reattaching flows based on modification of constant Prt is proposed. This modification is made using an empirical correlation between maximum Nusselt number and entrance Reynolds number. The model includes both the simplicity of Prt=0.9 assumption and the accuracy of two-equation heat-transfer models. Furthermore, an appropriate l...

A new eddy-based model for wall-bounded turbulent flows

Mixed 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...

Suitability of artificial bulk viscosity for large-eddy simulation of turbulent flows with shocks

The artificial bulk viscosity method to numerically capture shocks is investigated for largeeddy simulation (LES). Different variations of this method are tested on a turbulent flow over a cylinder at Reynolds number of 10,000 and free-stream Mach number of 0.85. The artificial bulk viscosity model by Cook and Cabot, which is parameterized by the strain rate magnitude, is found to provide unnec...

Large Eddy Simulation for Turbulent Flows

This thesis is concerned with one of the most promising approaches to the numerical simulation of turbulent flows, the Large Eddy Simulation (LES) in which the large scales of the flow are calculated directly, while the interactions with the small scales are modeled. Specifically, we analyze two new LES models, introduced in [30] and [51]. First, we sketch the derivation of the LES model introd...