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Molecular-to-Macro-Scale Control of Interfacial Behavior in Ebullient Phase Change in Aqueous Solutions of Reagents
Raj M. Manglik

Heat transport in boiling is governed by interfacial activity at dynamic gas-liquid-solid boundaries: the liquid-solid interface prognosticates wetting and nucleation of embryonic vapor bubbles, and the evolving liquid-vapor interface of bubbles affects dynamic surface tension, Marangoni convection, and the post-nucleation ebullient dynamics. At the micro-scale in this process, the transient transport mechanisms at the solid-liquid-vapor interfaces during nucleation and subsequent vapor-bubblegrowth dynamics (which essentially characterize macro-scale heat transport and the ebullient signature of boiling), can be altered by introducing small quantities of surface-active additives (reagents or polymers) in a pure liquid (water). The molecular characteristics of reagents affect and control this process; in fact, surface wetting and surface tension can be decoupled. This review delineates those aspects of micro-scale interfacial changes that are essentially caused at a molecular-scale by the relative adsorption-desorption of reagents at the liquid-vapor interface, and their physisorption and electrokinetics at the liquid-solid interface.

Keywords: Nucleate boiling; bubble dynamics; interfacial phenomena; enhanced heat transfer; wetting; interfacial tension.

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