A detailed mathematical model is developed that describes heat transfer through thin liquid films in the evaporator of heat pipes with capillary grooves. The model accounts for the effects of interfacial thermal resistance, disjoining pressure, and surface roughness for a given meniscus contact angle. The free surface temperature of the liquid film is determined using the extended Kelvin equation and the expression for interfacial resistance given by the kinetic theory. The numerical results obtained are compared to existing experimental data. The importance of the surface roughness and interfacial thermal resistance in predicting the heat transfer coefficient in the grooved evaporator is demonstrated.

Issue Section:
Heat Pipes
Keywords:
Evaporation, Heat Pipes and Thermosyphons, Thermocapillary Flows
Topics:
Evaporation, Heat pipes, Heat transfer
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