Heat transfer in cryogenic helium gas by turbulent Rayleigh-Bénard convection in a cylindrical cell of aspect ratio 1

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F14%3A00430597" target="_blank" >RIV/68081731:_____/14:00430597 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1088/1367-2630/16/5/053042" target="_blank" >http://dx.doi.org/10.1088/1367-2630/16/5/053042</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1367-2630/16/5/053042" target="_blank" >10.1088/1367-2630/16/5/053042</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Heat transfer in cryogenic helium gas by turbulent Rayleigh-Bénard convection in a cylindrical cell of aspect ratio 1

Popis výsledku v původním jazyce

We present experimental results on the heat transfer efficiency of cryogenic turbulent Rayleigh-Benard convection (RBC) in a cylindrical cell 0.3 m in both diameter and height which has improvements with respect to various corrections connected with finite thermal conductivity of sidewalls and plates. The heat transfer efficiency described by the Nusselt number Nu = Nu(Ra, Pr) is investigated for the range of Rayleigh number 10(6) < Ra < 10(15), with the Prandtl number varying such that 0.7 <= Pr < 15,using cryogenic He-4 gas with well-known and in situ tunable properties as a working fluid. For 7.2 x 10(6) < Ra < 10(11) our data (both corrected and uncorrected) agree with suitably corrected data from similar cryogenic experiments and are consistent with Nu proportional to Ra-2/7. Up to Ra similar or equal to 10(12), our data could be treated as Oberbeck-Boussinesq data. For Ra > 10(12), the heat transfer efficiency becomes affected by non-Oberbeck-Boussinesq (NOB) effects, causing as

Název v anglickém jazyce

Heat transfer in cryogenic helium gas by turbulent Rayleigh-Bénard convection in a cylindrical cell of aspect ratio 1

Popis výsledku anglicky

We present experimental results on the heat transfer efficiency of cryogenic turbulent Rayleigh-Benard convection (RBC) in a cylindrical cell 0.3 m in both diameter and height which has improvements with respect to various corrections connected with finite thermal conductivity of sidewalls and plates. The heat transfer efficiency described by the Nusselt number Nu = Nu(Ra, Pr) is investigated for the range of Rayleigh number 10(6) < Ra < 10(15), with the Prandtl number varying such that 0.7 <= Pr < 15,using cryogenic He-4 gas with well-known and in situ tunable properties as a working fluid. For 7.2 x 10(6) < Ra < 10(11) our data (both corrected and uncorrected) agree with suitably corrected data from similar cryogenic experiments and are consistent with Nu proportional to Ra-2/7. Up to Ra similar or equal to 10(12), our data could be treated as Oberbeck-Boussinesq data. For Ra > 10(12), the heat transfer efficiency becomes affected by non-Oberbeck-Boussinesq (NOB) effects, causing as

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BK - Mechanika tekutin

OECD FORD obor

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Projekt

<a href="/cs/project/GPP203%2F12%2FP897" target="_blank" >GPP203/12/P897: Rayleigh-Bénardova konvekce za kryogenních teplot pro Rayleigho čísla Ra > 1e11</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2014

Kód důvěrnosti údajů

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

Název periodika

New Journal of Physics

ISSN

1367-2630

e-ISSN

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Svazek periodika

16

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

40

Strana od-do

"053042: 1"-"40"

Kód UT WoS článku

000338940400001

EID výsledku v databázi Scopus

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