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Related papers: Dissipation of Quasiclassical Turbulence in Superf…

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We report on the extension of the experiments (P. M. Walmsley et al., Phys. Rev. Lett. 99, 265302 (2007)) on the decay of quasiclassical turbulence generated by an impulsive spin-down from angular velocity Omega to rest of superfluid 4He in…

Other Condensed Matter · Physics 2010-10-13 P. M. Walmsley , A. I. Golov , H. E. Hall , W. F. Vinen , A. A. Levchenko

Turbulence, produced by an impulsive spin-down from angular velocity Omega to rest of a cube-shaped container, is investigated in superfluid 4He at temperatures 0.08 K - 1.6 K. The density of quantized vortex lines L is measured by…

Other Condensed Matter · Physics 2011-11-10 P. M. Walmsley , A. I. Golov , H. E. Hall , A. A. Levchenko , W. F. Vinen

Turbulence in a superfluid in the zero temperature limit consists of a dynamic tangle of quantized vortex filaments. Different types of turbulence are possible depending on the level of correlations in the orientation of vortex lines. We…

Other Condensed Matter · Physics 2014-03-31 P. M. Walmsley , D. E. Zmeev , F. Pakpour , A. I. Golov

By injecting negative ions in superfluid 4He in the zero-temperature limit (T < 0.5 K), we generated tangles of quantized vortex line with negligible large-scale flow. For this quantum regime of superfluid turbulence, the vortex line length…

Other Condensed Matter · Physics 2008-10-01 P. M. Walmsley , A. I. Golov

There are two commonly discussed forms of quantum turbulence in superfluid $^4$He above 1K: in one there is a random tangle of quantizes vortex lines, existing in the presence of a non-turbulent normal fluid; in the second there is a…

Other Condensed Matter · Physics 2018-06-06 J. Gao , W. Guo , S. Yui , M. Tsubota , W. F. Vinen

Intermittency is a hallmark of turbulence, which exists not only in turbulent flows of classical viscous fluids but also in flows of quantum fluids such as superfluid $^4$He. Despite the established similarity between turbulence in…

Fluid Dynamics · Physics 2018-09-12 Emil Varga , Jian Gao , Wei Guo , Ladislav Skrbek

The energy dissipation of quasiclassical homogeneous turbulence in superfluid $^4$He (He II) is controlled by an effective kinematic viscosity $\nu'$, which relates the energy decay rate $dE/dt$ to the density of quantized vortex lines $L$…

Other Condensed Matter · Physics 2020-02-04 J. Gao , W. Guo , W. F. Vinen

The dynamics of quantized vortices is studied in superfluid 3He-B after a rapid stop of rotation. We use Andreev reflection of thermal excitations to monitor vortex motion with quartz tuning fork oscillators in two different experimental…

Other Condensed Matter · Physics 2012-07-20 Jaakko Hosio , Vladimir Eltsov , Matti Krusius , Jere Mäkinen

We describe measurements of the decay of pure superfluid turbulence in superfluid 3He-B, in the low temperature regime where the normal fluid density is negligible. We follow the decay of the turbulence generated by a vibrating grid as…

The flow of superfluid $^4$He around a translationally oscillating sphere, levitating without mechanical support, can either be laminar or turbulent, depending on the velocity amplitude. Below a critical velocity $v_c$ that scales as…

Other Condensed Matter · Physics 2017-11-17 Michael Niemetz , Risto Hänninen , Wilfried Schoepe

We report on the free decay of quasi-two-dimensional turbulence in superfluid $^4$He confined within nanofluidic channels. Using a pump-probe technique, we observe a complex decay of the vortex density $L(t)$ that deviates from a simple…

Fluid Dynamics · Physics 2026-03-04 Filip Novotný , Marek Talíř , Emil Varga

We report on studies of quantum turbulence with second-sound in superfluid 4He in which the turbulence is generated by the flow of the superfluid component through a wide square channel, the ends of which are plugged with sintered silver…

Other Condensed Matter · Physics 2015-09-07 Simone Babuin , Emil Varga , William F. Vinen , Ladislav Skrbek

Turbulence in superfluids depends crucially on the dissipative damping in vortex motion. This is observed in the B phase of superfluid 3He where the dynamics of quantized vortices changes radically in character as a function of temperature.…

Soft Condensed Matter · Physics 2009-11-11 V. B. Eltsov , M. Krusius , G. E. Volovik

Generation, statistically steady state, and temporal decay of axially rotating thermal counterflow of superfluid $^4$He (He~II) in a square channel is probed using the second sound attenuation technique, measuring the density of quantized…

The paper is concerned with the interpretation of many experiments that have been reported recently on the production of quantum turbulence by oscillating spheres, wires and grids in both 4He and 3He-B at temperatures so low that there is a…

Soft Condensed Matter · Physics 2011-02-23 R. Hänninen , M. Tsubota , W. F. Vinen

The dynamics of quantized vortices in rotating $^3$He-B is investigated in the low density (single-vortex) regime as a function of temperature. An abrupt transition is observed at $0.5 T_{\rm c}$. Above this temperature the number of vortex…

Soft Condensed Matter · Physics 2007-05-23 A. P. Finne , V. B. Eltsov , G. Eska , R. Hanninen , J. Kopu , M. Krusius , E. V. Thuneberg , M. Tsubota

Tangles of quantized vortex line of initial density ${\cal L}(0) \sim 6\times 10^3$\,cm$^{-2}$ and variable amplitude of fluctuations of flow velocity $U(0)$ at the largest length scale were generated in superfluid $^4$He at $T=0.17$\,K,…

Fluid Dynamics · Physics 2017-03-31 P. M. Walmsley , A. I. Golov

We report hot-wire measurements performed in two very different, co- and counter-rotating flows, in normal and superfluid helium at 1.6 K, 2 K, and 2.3 K. As recently reported, the power spectrum of the hot-wire signal in superfluid flows…

Observations of quantum turbulence in pure superfluid 4He in a rotating container are reported. New techniques of large-scale forcing (rotational oscillations of the cubic container) and detecting (monitoring ion transport along the axis of…

Other Condensed Matter · Physics 2012-09-25 P. M. Walmsley , A. I. Golov

The onset of turbulent flow around an oscillating sphere in superfluid $^4$He is known to occur at a critical velocity $v_c \sim \sqrt{\kappa\omega}$ where $\kappa$ is the circulation quantum and $\omega$ is the oscillation frequency. But…

Other Condensed Matter · Physics 2015-01-29 W. Schoepe , R. Hänninen , M. Niemetz
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