Experimental investigation on the thermal performance of a coiled heat exchanger using a new hybrid nanofluid

In this work the thermal performance of hybrid and single type nanofluid is investigated in a coiled heat exchanger at constant wall temperature and laminar flow operating conditions. The nanoparticle concentration is in the range of 0.1-0.4 vol% and the composition of the synthesized nanoparticle regarding hybrid nanofluid experiments is 97.5% alumina and 2.5% Ag. The maximum rate of heat transfer can be obtained by using the hybrid nanofluid at a concentration of 0.4 vol% which is 31.58% higher than that of the distilled water. Overall, the maximum thermal performance factor for hybrid nanofluid is about 2.55 suggesting the superior performance of the presented approach for energy intensification in heat exchangers. (C) 2016 Published by Elsevier Inc.