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ISSN Online: 2377-424X

ISBN Print: 0-89116-909-1

International Heat Transfer Conference 9
August, 19-24, 1990 , Jerusalem, Israel

POOL BOILING HEAT TRANSFER FROM PLAIN AND FINNED TUBES TO PROPANE AND PROPYLENE

Get access (open in a dialog) DOI: 10.1615/IHTC9.130
pages 75-80

要約

Results of heat transfer measurements are reported for pool boiling of propane and propylene from single, horizontal plain and finned copper tubes at saturation pressures between approx. 5 and 50 per cent of the critical pressure (corresponding to temperatures between approx. −23 and +50°C). The heat flux varies from free convection without bubble formation up to very intense nucleate boiling. The results for the finned tube with T-shaped fins and additional cavities as nucleation centers (Gewa-T-x tube) can be divided into three parts with different α, q - relationships: At intermediate heat fluxes, data in literature for other liquids are confirmed by the new results showing heat transfer coefficients with higher absolute values, but lower increases with heat flux and pressure for the finned tube than for the plain. At high fluxes and low pressures as well as low fluxes and high pressures, however, the heat transfer coefficient is approx. independent of the heat flux. This behaviour can be explained by a special form of bubble release from the gaps between the fins with tubes of the kind investigated.