The nonlinear theory of a "shear-current" effect in a nonrotating and nonhelical homogeneous turbulence with an imposed mean velocity shear is developed. The shear-current effect is associated with the W x J term in the mean electromotive force and causes the generation of the mean magnetic field even in a nonrotating and nonhelical homogeneous turbulence (where W is the mean vorticity and J is...

A wind tunnel investigation was performed to study the flow field over a 70° swept sharped edge delta wing model at high angles of attack. The experiments were conducted in the subsonic wind tunnel at the Department of Mechanical Engineering, Sharif University of Technology. Velocity profiles have been measured using a special pitot tube and hot wire anemometer at angles of attacks of 10 to 35 ...

this paper presents a k- turbulence model for simulation of steady current and itsinduced vortex shedding caused by the presence of an offshore pipeline. performance of the modelaround a circular cylinder above a wall with gap to diameter ratios of 0.1, 0.35 and 0.5 underdifferent flow regimes with reynolds numbers of 1500, 2500 and 7000 is studied. the flow field iscomputed with solving the re...

This reports the study on the flow behaviour, heat transfer and contamination distribution in a room. For this purpose the 3-D incompressible Navier-Stokes equations, energy equation and a mass transfer equation which model the concentration of contamination have been applied. For turbulence simulation the two equation standard k-  turbulence model was employed. By means of SIMPLE algorithm the...

Hybrid RANS/LES models, capable of transitioning through arbitrary levels modeled and resolved turbulence, aim to ameliorate both RANS deficiencies LES expense. We propose a method combining active forcing the flow field, where appropriate, with splitting standard single turbulence model into separate responsible for either unresolved stress or dissipation, which adapts that $i\phantom{\rule{0}...

Diagnostic atmospheric mass-consistent models generally are used together with turbulence parameterisations defined for flat terrain, thus in principle not able to catch the variability of the turbulence field induced by the presence of complex terrain and inhomogeneous conditions. The possibility of using prognostic turbulence fields produced accounting for the topography is then an appealing ...

Estimates of small-scale turbulence from numerical model output are produced from local estimates of the spatial structure functions of model variables such as velocity and temperature. The key assumptions used are the existence of a universal statistical description of small-scale turbulence and a locally universal spatial filter for the model variables. The shape of the model spatial filter i...