An analysis of the effects of various parameters on the average void fractions in subcooled boiling

Autor: P.G. Kroeger, Novak Zuber
Rok vydání: 1968
Předmět:
Zdroj: International Journal of Heat and Mass Transfer. 11:211-233
ISSN: 0017-9310
DOI: 10.1016/0017-9310(68)90151-8
Popis: An evaluation of the effects of various parameters on the ability to predict accurately the volumetric vapor concentration in subcooled boiling is presented. It is shown that: (1) the distribution parameter is of major importance as thermodynamic equilibrium is approached; (2) the point of incipient vapor formation greatly affects the void fraction in the subcooled regime—no reliable method for predicting this point exists at this time, and (3) it appears that the axial temperature distribution is of lesser effect. It is concluded, therefore, that the ability to predict the point of incipient vapor formation is mandatory for accurate prediction of the void fraction in subcooled boiling. Future research should thus be directed towards defining and predicting the location of this point. The results of the analysis also show that the conditions of the heated surface and the introduction of additives may have two effects on the void fraction in subcooled boiling. These effects are discussed and a method for taking them into account is presented. Satisfactory agreement is shown between predicted void fractions and recent experimental data obtained in subcooled boiling of Refrigerant-22 and of water over a wide pressure range.
Databáze: OpenAIRE