Improve Performance of Double Pipe Heat Exchanger by Using Zno/Water Nanofluid

The heat transfer of double tube heat exchanger under counter flow is experimentally investigated. Nanofluid and the pure water are used as cold and hot fluids respectively. ZnO nanoparticles of 30 nm diameter are dispersed in water to prepare nanofluid with mass concentrations of 0.5 and 1%. Cold nanofluid is flowing through the inner tube heat exchanger with 20°C temperature under 2, 4 and 6 lpm volume flow rate. The hot water enters the annular space of the heat exchanger at a temperature of 65°C and 4 lpm volume flow rate. To improve the performance of the heat exchanger, the experimental findings achieved using this sort of nanofluid will be compared to those obtained using pure water. The outcomes showed that employing nanofluid as the working fluid improved performance. When employing nanofluid, the highest heat exchanger effectiveness is 40 % for nanoparticles concentration of 0.5 % per mass and 54 % (with a mass concentration of 1 %) with a volume flow rate of 2 lpm.