Performance investigation of nano-structured composite surfaces for use in adsorption cooling systems with a mass recovery cycle

With an increase of the heat transfer coefficient and condensation rate in a condenser, a lower pressure can be achieved in a desorber, which leads to a dryer adsorber for the next adsorption phase and a better cooling performance in an adsorption cooling system. This study aims to experimentally investigate the condensation rate of different nano-structured surfaces and improve the cooling performance of an adsorption cooling system by coating a superhydrophobic-zeolite 13X adsorbent composite surface in the condenser. An experiment was designed and built to investigate the condensation rate of various nano-structured surfaces on a copper plate. The results show that a water collection rate (condensation rate) of the superhydrophobic–zeolite 13X adsorbent composite surface of 49.3 g/m² min is achieved, which shows an enhancement of about 50% compared to that of the copper surface. A mathematic model is developed to estimate the cooling performance of the adsorption cooling system utilizing the composite surface and a mass recovery cycle. The simulation results show that a SCP of 231.4 W/kg and a COP of 0.317 are determined, which shows an improvement of 25.0% and 7.8%, respectively, compared to that of the system without coating the nano-structured composite surface.