TITLE

Helium cryostat for experimental study of natural turbulent convection

AUTHOR(S)
Urban, P.; Hanzelka, P.; Kralik, T.; Musilova, V.; Skrbek, L.; Srnka, A.
PUB. DATE
August 2010
SOURCE
Review of Scientific Instruments;Aug2010, Vol. 81 Issue 8, p085103
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Published experiments on natural turbulent convection in cryogenic 4He gas show contradictory results in the values of Rayleigh number (Ra) higher than 1011. This paper describes a new helium cryostat with a cylindrical cell designed for the study of the dependence of the Nusselt number (Nu) on the Rayleigh number (up to Ra≈1015) in order to help resolve the existing controversy among published experimental results. The main part of the cryostat is a cylindrical convection cell of 300 mm in diameter and up to 300 mm in height. The cell is designed for measurement of heat transfer by natural convection at pressures ranging from 100 Pa to 250 kPa and at temperatures between 4.2 and 12 K. Parasitic heat fluxes into the convection medium are minimized by using thin sidewalls of the bottom and top parts of the cell. The exchangeable central part of the cell enables one to modify the cell geometry.
ACCESSION #
53422026

 

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