In this paper, the evaporative cooling characteristics using a super-hydrophilic screen mesh wick at the external surface of a condenser are experimentally and theoretically investigated to minimize the thermal management system for smart air mobilities such as UAMs (Urban Air Mobility), drones and so on. The super-hydrophilic screen mesh wicks with cooper mesh number 100, 150 and 200 are manufactured by using the immersion and heating processes. Using an experimental apparatus modeling the surface of the condenser attached to the screen mesh wick filled with water, the external thermal resistance is experimentally obtained by measuring temperatures under the constant heat flux condition. In addition, effects of heat flux and air velocity on the external thermal resistance of the condenser are experimentally presented. In the theoretical approach, porous medium approach for modeling the screen mesh wick is used to calculate the external thermal resistance of the condenser with a super-hydrophilic screen mesh wick during the evaporation. Especially, the evaporation from the surface of the water-filled screen mesh wick is considered by the water vapor density difference between the flowing air and the water filled in the screen mesh wick. It is shown that the theoretical results are well matched with experimental data. Moreover, using the theoretical model, we report the effects of the key engineering parameters such as effective pore radius and permeability of the wick, relative humidity, and velocity of the flowing air on the external thermal resistance. Finally, based on the results, it is shown that evaporative cooling using a porous media at the external surface of a condenser can remarkably reduce the external thermal resistance.