Simultaneous application of Al 2 O 3 nanoparticles and heat pipe in an air conditioning system

An analytical-numerical study on the thermal behavior of nanofluid in a cylindrical heat pipe is performed to investigate the nanofluid application in air conditioning systems. Pure water and Al2O3-water nanofluid are used as working fluids. A mathematical modeling is developed to predict the heat transferred by the heat pipe between precooling and reheating sections of the air conditioning system. The obtained results by proposed model are validated against experimental data and a good agreement between them is observed. The effect of nanoparticle concentration and size on the amount of energy required in precooling and reheating sections are evaluated. The results reveal that using nanofluid can dramatically decreases the temperature difference between condenser and evaporator sections of a cylindrical heat pipe under constant transferred thermal energy condition. Enhanced condition for precooling and reheating processes is provided for higher concentration and lower size of nanoparticles. Also, not a significant variation in heat transfer is observed by increasing nanoparticles size beyond 40 nm. The findings of this study prove the potential of nanofluid application for air conditioning of buildings located in regions with hot and humid climate.