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Indexed by:期刊论文

Date of Publication:2017-04-01

Journal:INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER

Included Journals:SCIE

Volume:107

Page Number:1129-1137

ISSN No.:0017-9310

Key Words:Homogeneous nucleation; Flash boiling; Boiling explosion; Bubble growth

Abstract:A series of new flash boiling sub-models inside a droplet were proposed in this study. Compared to the previous flash boiling model, the proposed model includes the classical homogeneous nucleation sub model, the Rayleigh bubble growth sub-model, and a new bubble explosion sub-model. Both the energy and momentum balances inside a droplet are considered. By coupling with the variation of the fuel thermo-physical properties with temperature, the criterion of the bubble nucleation, growth, and explosion criteria are well predicted. The model is validated by the experimental data of superheated water. The computational results indicate that the flash boiling process can be divided into three stages, i.e., the initial stage controlled by the surface tension of the fuel, the rapid growing stage controlled by the heat diffusion in the droplet, and the final explosion stage. Based on the present model, the boiling explosion time is quantitatively provided at wide ranges of fuel temperature and ambient pressure which have the vital significance in predicting the secondary breakup of the droplet. (C) 2016 Elsevier Ltd. All rights reserved.