Coherent propagation of vortex rings at extremely high Reynolds numbers

Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F22%3A10452857" target="_blank" >RIV/00216208:11320/22:10452857 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=2H4vervg5p" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=2H4vervg5p</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1017/jfm.2022.972" target="_blank" >10.1017/jfm.2022.972</a>

Result language
angličtina
Original language name
Coherent propagation of vortex rings at extremely high Reynolds numbers
Original language description
We take advantage of the extremely small kinematic viscosity of superfluid 4He to investigate the propagation of macroscopic vortex rings at Reynolds numbers between 2 x 10(4) and 4 x 10(6). These inhomogeneous flow structures are thermally generated by releasing short power pulses into a small volume of liquid, open to the surrounding bath through a vertical tube 2 mm in diameter. We study specifically the ring behaviour between 1.30 and 1.80 K using the flow visualization and second sound attenuation techniques. From the obtained data sets, containing more than 2600 realizations, we find that the rings remain well-defined in space and time for distances up to at least 40 tube diameters, and that their circulation depends significantly on the travelled distance, in a way similar to that observed for turbulent vortex rings propagating in Newtonian fluids. Additionally, the ring velocity and circulation appear to be influenced solely by a single, experimentally accessible parameter, combining the liquid temperature with the magnitude and duration of the power pulse. Overall, our results support the view that macroscopic vortex rings moving in superfluid He-4 closely resemble their Newtonian analogues, at least in the absence of significant thermal effects and at sufficiently large flow scales.
Czech name
—
Czech description
—

Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Project
<a href="/en/project/GA19-00939S" target="_blank" >GA19-00939S: Dynamics of large vortices in quantum turbulence</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Similar results(10)