In this paper, the homogeneous nucleation boiling phenomena under non-equilibrium liquid heating condition has been reviewed and analyzed by using a recently developed theoretical model. Three different liquid heating cases has been considered in this model, namely (i) linearly increasing boundary temperature condition, (ii) high heat flux pulse heating condition and (iii) constant boundary temperature condition that includes almost all earlier experimental studies of homogeneous boiling under non-equilibrium condition. In this model, a finite liquid control volume or cluster having the size of a characteristic critical embryo at the liquid boundary has been considered and the corresponding energy balance equation is obtained by considering two parallel competing processes taking place inside the liquid cluster, namely, transient external energy deposition and internal energy consumption due to bubble nucleation and growth. Depending on the instantaneous rate of external energy deposition and boiling heat consumption within the liquid cluster, a particular state has been defined as the condition of boiling explosion i.e. the onset of mass scale vaporization in which the bubble generation and its growth causes the liquid sensible energy to decrease. The obtained results have been presented in terms of the average temperature rise within the liquid cluster, maximum attainable liquid temperature prior to the boiling explosion and the time required for achieving the condition of the boiling explosion for various liquid heating cases. With the initial and boundary conditions identical to those reported in literature, model results have been found to be in good agreement with the experimental observations for all of these liquid heating cases. The boiling explosion condition as predicted by the developed model has been verified by comparing the heat flux across the liquid-vapor interface at the boiling explosion with the corresponding limit of maximum possible heat flux, qmax,max. Also, the limiting condition for the occurrence of homogeneous boiling explosion in water at atmospheric pressure has been determined by applying the present model for any liquid heating condition.
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