Key words hydrodynamics – methods: numerical – turbulence We determine the timescales associated with turbulent decay and isotropization in closure models using anisotropically forced and freely decaying turbulence simulations and study the applicability of these models. We compare the results from anisotropically forced three-dimensional numerical simulations with the predictions of the closur...

The k v model has been investigated to quantify its predictive performance on two high lift con gurations D ow over a single element aerofoil involving closed type separation D ow over a prolate spheroid involving open type separation A code friendly modi cation has been proposed which enhances the numerical stabil ity in particular for explicit and uncoupled ow solvers As a result of introduci...

The derivation of the space averaged Navier–Stokes equations for the large eddy simulation (LES) of turbulent incompressible ows introduces two groups of terms which do not depend only on the space averaged ow eld variables: the divergence of the Reynolds stress tensor and commutation errors. Whereas the former is studied intensively in the literature, the latter terms are usually neglected. Th...

We investigate the nonlinear dynamics of turbulent shear flows, with and without rotation, in the context of a simple but physically motivated closure of the equation governing the evolution of the Reynolds stress tensor. We show that the model naturally accounts for some familiar phenomena in parallel shear flows, such as the subcritical transition to turbulence at a finite Reynolds number and...

Numerical predictions of blood flow patterns and hemodynamic stresses in Abdominal Aortic Aneurysms (AAAs) are performed in a two-aneurysm, axisymmetric, rigid wall model using the spectral element method. Homogeneous, Newtonian blood flow is simulated under steady conditions for the range of Reynolds numbers 10 < or =Re < or =2265. Flow hemodynamics are quantified by calculating the distributi...

For H-type transition to turbulence in a flat-plate boundary layer, we identify dynamically important features resulting from direct numerical and large eddy simulations (DNS and LES, respectively). Even though LES coupled with a dynamic subgrid-scale model provides an accurate prediction of the transition location, it fails to predict initial overshoot and subsequent turbulent skin friction. D...

Rayleigh-Bernard convection offers a unique flow situation in which buoyancy-generated turbulence can be studied in isolation, free of the complicating influence of shear production of turbulence. The objective of this paper is to examine and model important aspects of buoyancy-generated turbulence using direct numerical simulation (DNS) data of Rayleigh-Bernard convection. In particular, we ex...

April 10-15, 2016 Abstract Recent theoretical results are presented from our ongoing study investigating the distinct convective instability properties of the boundary-layer flow over rough rotating disks. In this study, radial anisotropic surface roughness (concentric grooves) is modelled using the partial-slip approach of Miklavčič & Wang (2004) and the surface-geometry approach of Yoon et. a...