Derivations of Correlation and Model of Transition Boiling Heat Transfer: Liquid-Solid Contact Model for Transition Boiling Heat Transfer in High Wall Superheat

Abstract

The transition boiling heat transfer was examined through derivations of correlation and model. The correlation of liquid-solid contact fraction in transition boiling was derived by focusing on the dimensionless wall temperature, Θ = (Tw−TCHF) / (TMHF−TCHF); the following correlation was obtained from experimental results for water, R-113 and LN2: Γ = 1.000 − 0.9120Θ − 0.1343Θ2, where qtb = qCHFΓ+qMHF(1−Γ). In the present model, considering a pseudo liquid-solid contact right after detachment of a bubble from liquid-vapor interface resulted from Rayleigh-Taylor instability, transient heat conduction was analyzed in it three dimensionally. Liquid-solid contact time and area were given by the present correlation of the fractions of liquid-solid contact: τcontact = 0.3Γt, Awet = 15 × 15 Γa, Γ = Γt Γa = 1.000 − 0.9120Θ − 0.1343Θ2, where Θ = (Tw−TCHF)/(TMHF−TCHF). The prediction by the present model was in agreement with the present experimental data for water.