Abstract
The effects of pressure on heat transfer from a horizontal copper surface immersed in pressurized He I are experimentaly investigated. Heat transfer surface is 0.02m in diameter. The pressure is varied from 0.047MPa to 1.1MPa and helium temperature is varied from 3.0K to 5.0K. The data obtained are divided into two heat transfer regions, the subcooled heat transfer region and supercritical heat transfer region. Heat transfer in subcooled liquid helium are correlated with a modified Rohsenow equation based on saturation temperature difference. Peak nucleate boiling heat fluxes obtained in subcooled helium increase with subcooling and show two different slope in large subcooling. Heat transfer in liquid helium pressurized above critical pressure show a good agreement with a equation predicted from heat transfer in ordinary liquid.
