in this study, changes in speed and turbulence intensity in the wake of a peugeot model and the drag coefficient changes with increases vehicle speed in unsteady flow measured and evaluated. the blow open circuit wind tunnel to simulate fluid flow is used. disturbances and nominal maximum speed of the device, respectively is, 30 m / s and 0.01%. has been continuously increasing speed by an inve...

The rotational influence on the eddy-diffusivity tensor Dij for anisotropic turbulence fields is considered in order to explain the lithium decay law during the spin-down process of solar-type stars. Rotation proves to be highly effective in the transfer of chemicals through the solar tachocline (beneath the convection zone) which is assumed to contain only turbulence with horizontal motions. T...

Observations of quantum turbulence in pure superfluid 4He in a rotating container are reported. Large-scale forcing through rotational oscillations of the cubic container and detecting of turbulence via monitoring ion transport along the axis of rotation were used. Near the axial walls, with increasing forcing the vortex tangle grows without an observable threshold. This tangle gradually develo...

Previous studies have shown that the isoplanatic distortion due to turbulence and the image of a remote object may be jointly estimated from the 4D mutual intensity across an aperture. This Letter shows that decompressive inference on a 2D slice of the 4D mutual intensity, as measured by a rotational shear interferometer, is sufficient for estimation of sparse objects imaged through turbulence....

in this study, the characteristics of the wake around a rotating circular cylinder have been investigated experimentally. to this end, a cylinder with a circular cross-section of plexiglas with the length of 400 mm and a diameter of 20 mm have been tested in the wind tunnel. using existing methods, the characteristics of the wake and the drag coefficients of the model in different cases have be...

Local hydromagnetic simulations of accretion disc turbulence provide now the most convincing evidence that the origin of turbulence in discs could be the Balbus{Hawley magneto-rotational instability. The main results of such calculations are highlighted with particular emphasis on the generation of large scale magnetic elds. Comparison with mean-eld dynamo theory is made. This theory is then us...

The Langevin equation and its adaptations can reproduce accurately key aspects of fluid-particle motions in turbulent flows including: ballistic and normal-diffusive transport regimes, Lagrangian velocity autocorrelation functions and integral Lagrangian timescales. More recently it has become apparent that trajectory-rotations are also important dynamical quantities and that non-zero mean rota...

Recent simulations of supernova-driven turbulence within the ISM support the existence of a large-scale dynamo. With a growth time of about two hundred million years, the dynamo is quite fast – in contradiction to many assertions in the literature. We here present details on the scaling of the dynamo effect within the simulations and discuss global meanfield models based on the adopted turbulen...

A turbulence-affected mechanism of formation of zonal winds in the Earth’s troposphere is discussed from the perspective of the theory of rotationally anisotropic turbulence (the RAT theory). The turbulence effect is explained as an action of the turbulence rotational viscosity introduced within the RAT theory to characterize the shear in relative rotation (determined as the difference between ...