HEAT-TRANSFER DURING EVAPORATION ON CAPILLARY-GROOVED STRUCTURES OF HEAT PIPES

A detailed mathematical model is developed that describes heat transfe r through thin liquid films in the evaporator of heat pipes with capil lary grooves. The model accounts for the effects of interfacial therma l resistance, disjoining pressure, and surface roughness for a given m eniscus contact angle. The free surface temperature of the liquid film is determined using the extended Kelvin equation and the expression f or interfacial resistance given by the kinetic theory. The numerical r esults obtained are compared to existing experimental data. The import ance of the surface roughness and interfacial thermal resistance in pr edicting the hear transfer coefficient in the grooved evaporator is de monstrated.