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ISSN Online: 2377-424X

ISBN Print: 0-85295-345-3

International Heat Transfer Conference 10
August, 14-18, 1994, Brighton, UK

Nucleate Boiling Heat Transfer from a Localized Heat Source to Ethylene Glycol/Water Mixtures

Get access (open in a dialog) DOI: 10.1615/IHTC10.4670
pages 117-122

Abstract

Nucleate boiling heat transfer characteristics for a localized heat source immersed in an ethylene glycol/water mixture are reported for a wide range of mixture compositions. Highly accurate predictions of binary mixture properties have been used to generate property information for the mixtures tested. In many previous studies of binary mixture boiling, water and alcohol mixtures have been used as test fluids. The property variations of ethylene glycol/water mixtures with concentration are distinctly different from those of alcohol/water mixtures. As increasing amounts of alcohol are added to water at a fixed pressure, the surface tension decreases, the bubble point temperature decreases, and the latent heat first decreases rapidly and then very slowly. In contrast, adding ethylene glycol to water at fixed pressure decreases the surface tension, increases the bubble point temperature, and the latent heat decreases slowly at first and then rapidly at high concentrations. These property variation differences for ethylene glycol/water mixtures provide an opportunity to examine how these properties affect nucleate boiling heat transfer in a binary mixture. To this end, a series of experiments were conducted to measure nucleate boiling heat transfer from a localized upward-facing surface immersed in binary ethylene glycol/water mixtures. These studies were also motivated by the potential importance of ethylene glycol/water mixtures as working fluids in thermal control systems. Boiling heat transfer data were obtained for the pure water and pure ethylene glycol for comparison. The data reported here were taken at subatmospheric pressures < 101 kPa). Currently-available methods for correlating binary mixture pool boiling data are evaluated against the heat transfer data obtained in this study, and those providing the best fit to these data are identified.