Search results for "Vortex stretching"

showing 3 items of 3 documents

Vortex diffusion and vortex-line hysteresis in radial quantum turbulence

2014

Abstract We study the influence of vortex diffusion on the evolution of inhomogeneous quantized vortex tangles. A simple hydrodynamical model to describe inhomogeneous counterflow superfluid turbulence is used. As an illustration, we obtain solutions for these effects in radial counterflow of helium II between two concentric cylinders at different temperatures. The vortex diffusion from the inner hotter cylinder to the outer colder cylinder increases the vortex length density everywhere as compared with the non-diffusive situation. The possibility of hysteresis in the vortex line density under cyclical variations of the heat flow is explored.

PhysicsCondensed matter physicsTurbulenceHysteresisVortex diffusionQuantum turbulenceStarting vortexCondensed Matter PhysicsQuantum turbulenceElectronic Optical and Magnetic MaterialsVortexVortex ringCondensed Matter::SuperconductivityVortex stretchingHorseshoe vortexQuantized vorticeBurgers vortexElectrical and Electronic EngineeringSettore MAT/07 - Fisica MatematicaPhysica B: Condensed Matter
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Troubled cosmic flows: turbulence, enstrophy and helicity from the assembly history of the intracluster medium

2021

Both simulations and observations have shown that turbulence is a pervasive phenomenon in cosmic scenarios, yet it is particularly difficult to model numerically due to its intrinsically multiscale character which demands high resolutions. Additionally, turbulence is tightly connected to the dynamical state and the formation history of galaxies and galaxy clusters, producing a diverse phenomenlogy which requires large samples of such structures to attain robust conclusions. In this work, we use an adaptive mesh refinement (AMR) cosmological simulation to explore the generation and dissipation of turbulence in galaxy clusters, in connection to its assembly history. We find that major mergers…

PhysicsCosmology and Nongalactic Astrophysics (astro-ph.CO)Accretion (meteorology)TurbulenceFOS: Physical sciencesAstronomy and AstrophysicsAstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsVorticityEnstrophyAstrophysics - Astrophysics of GalaxiesGalaxySpace and Planetary ScienceAstrophysics of Galaxies (astro-ph.GA)Vortex stretchingIntracluster mediumGalaxy clusterAstrophysics::Galaxy AstrophysicsAstrophysics - Cosmology and Nongalactic Astrophysics
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Energy and temperature of superfluid turbulent vortex tangles

2007

We consider three aspects of turbulent vortex tangles in superfluids. First, we outline some contributions to the Vinen’s equation for the time evolution of the vortex line density, related to the presence of pinned vortices incorporating the effects of the walls. Afterwards, we analyze some aspects of the energy balance of the vortex tangle, related to frictional dissipation and to vortex formation and destruction. Finally, we explore the concept of an effective temperature for the vortex tangle, related to the average energy of the vortex loops and to the diffusion coefficient of vortex lines. The combination of these ideas suggests some formal similarities with other kinds of driven none…

Quantum fluidPhysicsTurbulenceNon-equilibrium thermodynamicsDissipationCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsVortexSuperfluidityClassical mechanicsCondensed Matter::SuperconductivityVortex stretchingBurgers vortexSettore MAT/07 - Fisica MatematicaQuantum turbulence. Superfluid helium. Vinen equation.Physical Review B
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