Vorticity enhancement in thermal counterflow of superfluid helium

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F18%3A10378133" target="_blank" >RIV/00216208:11320/18:10378133 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1103/PhysRevB.97.064512" target="_blank" >https://doi.org/10.1103/PhysRevB.97.064512</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.97.064512" target="_blank" >10.1103/PhysRevB.97.064512</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Vorticity enhancement in thermal counterflow of superfluid helium

Popis výsledku v původním jazyce

The dynamics of relatively small particles in steady-state thermal counterflow of superfluid He-4 (He II) is experimentally investigated by using the particle tracking velocimetry technique. We find that, close to the heat source, the mean distance between quantized vortices, representing the quantum length scale of the flow, is apparently about one order of magnitude smaller than that expected in the bulk, at the same temperature and heat flux. Possible physical mechanisms leading to this significant vorticity enhancement in the heater proximity are discussed and strongly support the view that the geometry of the channel where thermal counterflow occurs has a relevant influence on the observed flow features. Boundary and entrance effects, which have received little attention to date, should therefore be included in a comprehensive description of He II turbulent flows.

Název v anglickém jazyce

Vorticity enhancement in thermal counterflow of superfluid helium

Popis výsledku anglicky

The dynamics of relatively small particles in steady-state thermal counterflow of superfluid He-4 (He II) is experimentally investigated by using the particle tracking velocimetry technique. We find that, close to the heat source, the mean distance between quantized vortices, representing the quantum length scale of the flow, is apparently about one order of magnitude smaller than that expected in the bulk, at the same temperature and heat flux. Possible physical mechanisms leading to this significant vorticity enhancement in the heater proximity are discussed and strongly support the view that the geometry of the channel where thermal counterflow occurs has a relevant influence on the observed flow features. Boundary and entrance effects, which have received little attention to date, should therefore be included in a comprehensive description of He II turbulent flows.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/GA16-00580S" target="_blank" >GA16-00580S: Hranice kvantové turbulence</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review B

ISSN

2469-9950

e-ISSN

—

Svazek periodika

97

Číslo periodika v rámci svazku

6

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

—

Kód UT WoS článku

000425090500003

EID výsledku v databázi Scopus

2-s2.0-85042143542