Comparative study by numerical investigation of heat transfer in circular tube by using hybrid nanofluids

Abstract

Heat exchangers have bagged a noteworthy role in industrial and commercial applications with the passage of time. Heat transfer augmentation of the heat exchanger by using hybrid nanofluid has picked up lot of recognition due to its desirable thermal properties. In the current numerical investigation, thermal performance of tubular heat exchanger for turbulent flow owing to the use of Al2O3-SiO2/water and AlN-Al2O3/water at different volume concentrations was analyzed. Uniform heat flux of 7000 W/m2 was given around the tube and simulated by varying Reynolds number from 5000 to 10000 with the use of ANSYS FLUENT. Computational results were validated with the available literature. The obtained results signified that Nusselt number in each case has been raised and friction factor got lowered with an increase in Reynolds number. Hybrid nanofluids have shown high grade thermal characteristics as compared to water which is used as base fluid in the present study. Observations revealed that 0.6% AlN-1.4% Al2O3/water given high heat transfer rate among other AlN-Al2O3/water volume concentrations. 0.2% Al2O3-1.8% SiO2/water exhibited high thermal properties as compared with other Al2O3-SiO2/water volume concentrations. Final outcome revealed that Al2O3-SiO2/Water has given better heat transfer augmentation compared to AlN-Al2O3/water and base fluid at each Reynolds number. Superior heat transfer characteristics were achieved at 0.2% Al2O3-1.8% SiO2/water loading among all computations.