Nanoparticles Effects on Heat Transfer Characteristics

Abstract

A comparative study and results analysis performed, for evaluating the average heat transfer rate, overall heat transfer coefficient, convective heat transfer coefficient and Nusselt number, through corrugated plate heat exchanger, by using Nano particles of MWCNT dispersed in DI water, using three different concentrations of Multi-Walled Carbon Nanotubes(MWCNT) of 0.25 g/liter (0.00961 vol.%), 0.5 g/liter (0.0192vol.%) and 1 g/liter (0.0384vol.%). Besides, the variation of the hot Nano-DI water inlet temperature to the heat exchanger at 50 0C, 60 0C, 70 0C and 80 0C, and by varying the volume flow rate of the hot Nano-DI water side at 1 LPM, 2 LPM, 3 LPM, 4 LPM and 5 LPM, and varying volume flow rate of the cold water side at 1 LPM, 2 LPM, 3 LPM, 4 LPM and 5 LPM.It is observed that average heat transfer rate, overall heat transfer coefficient, convective heat transfer coefficient and Nusselt number of nanofluid increase, by increasing the volume flow rate of the hot fluid side, and byincreasing the volume flow rates of the cold fluid side, andby increasing the inlet temperature of the hot fluid side, and by increasing the Nano particles concentration in the DI water.The 1 g/liter concentrationreaches 47.5% enhancement in average heat transfer rate,53.5% enhancement in overall heat transfer coefficient,68.8% enhancement in convective heat transfer coefficient and33.3% enhancement in Nusselt number, over the DI water at 80 0C andѶh= 5 LPM, to become higher than that of DI water,0.25 g/liter and 0.5 g/liter samples. New correlations for estimating the Nu number and friction factor are obtained. Comparisons with previous researches were done also