The present work investigates the influence of a self-rewetting n-butanol aqueous solution on enhanced nucleate boiling heat transfer. This influence was investigated on mechanically treated surfaces and on etched surfaces. Surface characteristics were evaluated through SEM imaging, by measurement of contact angle and Raman spectroscopy. Pool boiling experimental setup constructed by the Laboratory for thermal technology was used to determine the boiling heat transfer characteristics of treated surfaces during saturated boiling of pure water and self-rewetting fluid at various concentrations. During experiments we recorded boiling curves and other relevant data to evaluate the boiling performance. Critical heat flux using pure water on mechanically treated surfaces reached up to 1285 kW m-2 and up to 1836 kW m-2 on etched surfaces, while the heat transfer coefficients reached 54.7 kW m-2 K-1 and 62.2 kW m-2 K-1, respectfully. By using self-rewetting fluids on mechanically treated surfaces we reached higher critical heat fluxes, while boiling of such fluids on etched surfaces resulted in lower critical heat fluxes than achieved with pure water. Through SEM imaging we observed changes of the surface after boiling of self-rewetting fluids on both surfaces. We estimate that a chemical reaction of copper compounds with n-butanol took place on the boiling surfaces.
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