English
Related papers

Related papers: Random Vortex-Street Model for a Self-Similar Plan…

200 papers

The relationship between observed variability time and emission region geometry is explored for the case of emission by relativistic jets. The approximate formula for the jet-frame size of the emission region, $R'=Dc\Delta t_{\rm obs}$ is…

Astrophysics · Physics 2009-11-07 R. J. Protheroe

A three-dimensional round liquid jet within a low-speed coaxial gas flow is numerically simulated and explained via vortex dynamics ($\lambda_2$ method). The instabilities on the liquid-gas interface reflect well the vortex interactions…

Fluid Dynamics · Physics 2018-08-28 Arash Zandian , William A. Sirignano , Fazle Hussain

Experiments and numerical simulations were conducted to investigate the dispersion of turbulent jets issuing from realistic pipe geometries. The effect of jet densities and Reynolds numbers on vertical buoyant jets were investigated, as…

Fluid Dynamics · Physics 2018-11-15 Majid Soleimani Nia , Brian Maxwell , Peter Oshkai , Nedjib Djilali

Planetary turbulence is observed to self-organize into large-scale structures such as zonal jets and coherent vortices. One of the simplest models that retains the relevant dynamics of turbulent self-organization is a barotropic flow in a…

Atmospheric and Oceanic Physics · Physics 2015-01-22 Nikolaos A. Bakas , Petros J. Ioannou

A longstanding mystery about Jupiter has been the straightness and steadiness of its weather-layer jets, quite unlike terrestrial strong jets with their characteristic unsteadiness and long-wavelength meandering. The problem is addressed in…

Earth and Planetary Astrophysics · Physics 2019-07-29 Stephen I. Thomson , Michael E. McIntyre

The internal interactions of fluids occur at all scales therefore the resulting force fields have no reason to be smooth and differentiable. The release of the differentiability hypothesis has important mathematical consequences, like scale…

General Physics · Physics 2013-03-15 Louis de Montera

Turbulent signals are known to exhibit burst-like activities, which affect the turbulence statistics at both large and small scales of the flow. In our study, we pursue this problem from the perspective of an event-based framework, where…

Fluid Dynamics · Physics 2023-01-26 Subharthi Chowdhuri , Tirtha Banerjee

The separating and reattaching turbulent flow past a rectangular cylinder is studied to describe how small and large scales contribute to the sustaining mechanism of the velocity fluctuations. The work is based on the Anisotropic…

Fluid Dynamics · Physics 2022-08-24 Alessandro Chiarini , Davide Gatti , Andrea Cimarelli , Maurizio Quadrio

This thesis presents a newly developed theory for the formation and maintenance of eddy-driven jets in planetary turbulence. The novelty is that jet formation and maintenance is studied as a dynamics of the statistics of the flow rather…

Atmospheric and Oceanic Physics · Physics 2019-04-09 Navid C. Constantinou

New two- and three-dimensional calculations are presented of relativistic jet propagation and break out in massive Wolf-Rayet stars. Such jets are thought responsible for gamma-ray bursts. As it erupts, the jet is surrounded by a cocoon of…

Astrophysics · Physics 2009-11-10 Weiqun Zhang , S. E. Woosley , A. Heger

We study the phenomena associated with the low-velocity impact of two solid discs of equal size using a cell model of brittle solids. The fragment ejection exhibits a jet-like structure the direction of which depends on the impact…

Condensed Matter · Physics 2015-06-25 F. Kun , H. J. Herrmann

We examine the propagation of 2-dimensional relativistic jets through the stellar progenitor in the collapsar model for gamma-ray bursts. In agreement with previous studies, we find that relativistic jets are collimated by their passage…

Astrophysics · Physics 2009-11-07 Weiqun Zhang , S. E. Woosley , A. I. MacFadyen

Jet fragmentation is investigated through a Direct Numerical Simulation campaign using Basilisk (Popinet & collaborators 2013). The simulations span over one order of magnitude of gaseous Weber numbers (13 to 165), i.e. over the second…

Fluid Dynamics · Physics 2023-07-25 Romain Vallon , Malek Abid , Fabien Anselmet

Circular flush Jets In Cross-Flow were experimentally studied in a water tunnel using Volumetric Particle Tracking Velocimetry, for a range of jet to cross-flow velocity ratios, r, from 0.5 to 3, jet exit diameters $d$ from 0.8 cm to 1 cm…

Fluid Dynamics · Physics 2013-06-27 T. Cambonie , N. Gautier , J. -L. Aider

Isolated turbulent bands observed in transitional channel flows have downstream heads and inclined bulks at a characteristic angle. In the large-scale mean flow, a $\nu$-shape vortex found at the head elongates into the bulk part, forming a…

Fluid Dynamics · Physics 2023-10-06 Linsen Zhang , Jianjun Tao

At sufficiently large transport currents $I_\mathrm{tr}$, a defect at the edge of a superconducting strip acts as a gate for the vortices entering into it. These vortices form a jet, which is narrow near the defect and expands due to the…

Radio maps of AGNs often show linear features, called jets, both on pc as well as kpc scales. These jets supposedly possess relativistic motion and are oriented close to the line of sight of the observer and accordingly the relativistic…

Astrophysics of Galaxies · Physics 2016-08-11 Ashok K. Singal

The amplitude of jet distortions and accompanying pressure and velocity fluctuations resulting from Kelvin-Helmholtz instability of three dimensional relativistic jets are explored. The effect of instability on jets as they accelerate from…

Astrophysics · Physics 2007-05-23 P. E. Hardee , A. Rosen , P. A. Hughes , G. C. Duncan

Jet breaks in gamma ray burst (GRB) afterglows provide a direct probe of their collimation angle. Modeling a jet break requires an understanding of the "jet spreading" process, whereby the jet transitions from a collimated outflow into the…

High Energy Astrophysical Phenomena · Physics 2018-10-10 Paul C. Duffell , Tanmoy Laskar

Flapping and revolving wings can produce attached leading edge vortices (LEVs) when the angle of attack is large. In this work, a low order model is proposed for the edge vortices that develop on a revolving plate at 90 degrees angle of…

Fluid Dynamics · Physics 2018-10-12 Di Chen , Dmitry Kolomenskiy , Hao Liu