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Steady propagation of the vaporization front in metastable liquid / S. P. Aktershev in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 132 N° 10 (Octobre 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 10 (Octobre 2010) . - 05 p. Titre : Steady propagation of the vaporization front in metastable liquid Type de document : texte imprimé Auteurs : S. P. Aktershev, Auteur ; V. V. Ovchinnikov, Auteur Année de publication : 2011 Article en page(s) : 05 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Bubbles  Convection  Film  boiling  Metastable  states  Nuclear  power  stations  Vaporisation Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The boiling up of a metastable liquid when the vaporization fronts appear is considered theoretically and experimentally. Boiling up occurs usually on the surface of a heater. At the first stage, the growth of a spherical vapor bubble is observed. If the temperature of liquid exceeds the threshold value, the vaporization fronts develop near to the line of contact of a vapor bubble and heater. Fronts of vaporization extend along a heater with constant speed. It is a direct transition from one phase convection to film boiling. Such scenario of crisis of a convective heat transfer is also possible in the nuclear reactor equipment. The model of steady propagation of the vaporization front is developed. The temperature and velocity of propagation of the interface are determined from the balance equations for the mass, momentum, and energy in the neighborhood of the vaporization front and the condition of stability of motion of the interface. It is shown that a solution of these equations exists only if the liquid is heated above a threshold value. The velocity of propagation of the vaporization front also has a threshold value. The calculated velocity of the interface motion and the threshold value of temperature are in reasonable agreement with available experimental data for various liquids within wide ranges of saturation pressures and temperatures of the overheated liquid. The developed model adequately describes the experimental data for various substances in a wide range of temperature of an overheated fluid. In this model, the steady propagation of the vaporization front is possible only if the temperature of a metastable liquid exceeds some threshold value. The velocity of the vaporization front also has a threshold value. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] [article] Steady propagation of the vaporization front in metastable liquid [texte imprimé] / S. P. Aktershev, Auteur ; V. V. Ovchinnikov, Auteur . - 2011 . - 05 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 10 (Octobre 2010) . - 05 p. Mots-clés : Bubbles  Convection  Film  boiling  Metastable  states  Nuclear  power  stations  Vaporisation Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The boiling up of a metastable liquid when the vaporization fronts appear is considered theoretically and experimentally. Boiling up occurs usually on the surface of a heater. At the first stage, the growth of a spherical vapor bubble is observed. If the temperature of liquid exceeds the threshold value, the vaporization fronts develop near to the line of contact of a vapor bubble and heater. Fronts of vaporization extend along a heater with constant speed. It is a direct transition from one phase convection to film boiling. Such scenario of crisis of a convective heat transfer is also possible in the nuclear reactor equipment. The model of steady propagation of the vaporization front is developed. The temperature and velocity of propagation of the interface are determined from the balance equations for the mass, momentum, and energy in the neighborhood of the vaporization front and the condition of stability of motion of the interface. It is shown that a solution of these equations exists only if the liquid is heated above a threshold value. The velocity of propagation of the vaporization front also has a threshold value. The calculated velocity of the interface motion and the threshold value of temperature are in reasonable agreement with available experimental data for various liquids within wide ranges of saturation pressures and temperatures of the overheated liquid. The developed model adequately describes the experimental data for various substances in a wide range of temperature of an overheated fluid. In this model, the steady propagation of the vaporization front is possible only if the temperature of a metastable liquid exceeds some threshold value. The velocity of the vaporization front also has a threshold value. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...]