Microlayer evaporative mechanism

Microlayer evaporative mechanism (Fig. 2.19c) Section 2.2.5.5 gives the model for this mechanism. A theoretical heat transfer rate is possible through evaporation of a fluid into a receiver ... 

Figure 2.24 Comparison of experimental results of bubble period with predictions of a model involving different mechanisms (a) nucleate boiling only (b) nucleate boiling and natural convection (c) nucleate boiling, natural convection, and microlayer evaporation. (From Judd, 1989. Copyright 1989 by American Society of Mechanical Engineers, New York. Reprinted with permission.)...

Judd (1989) interpreted experimental results of Ibrahim and Judd (1985), in which the bubble period first increased and then decreased as subcooling varied over the range 0 < (7 t - Tm) < 15°C (27°F), by means of a comprehensive model incorporating the contributions of nucleate boiling, natural convection, and microlayer evaporation components. The mechanism responsible for the nucleation of bubbles at exactly the frequency required at each level of subcooling is the subject of their continuing research. 

Correlations for Boiling Heat Transfer Nucleate boiling is a complex phenomenon. Several mechanisms have been proposed to explain the boiling process, such as latent heat transport, microconvection, vapor-liquid exchange, wake flow, enhanced convection, and microlayer evaporation, details of which can be found in Ginoux (1978). 

Evaporation-of-microlayer theory. A later hypothesis for the mechanism of nucleate boiling considers the vaporization of a micro layer of water underneath the bubble. This was first suggested by Moore and Mesler (1961), who measured... 

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