Heat transfer analysis of triple concentric tube heat exchanger using MWCNT/water nanofluids under parallel flow configurations

In this investigation, heat transfer characteristics of Multi-Walled Carbon Nanotubes/water nanofluids are studied experimentally in a triple concentric tube heat exchanger under parallel flow configurations and compared with water. The Multi-Walled Carbon Nanotubes/water nanofluids are formulated for 0.2, 0.4 and 0.6% nanoparticle volume concentrations using a two-step method by adding sodium dodecylbenzene sulfonate surfactant. At 0.6% particle volume concentration, the Nusselt number is found to be 10% higher compared with water at 7500 Reynolds number. In this experimental investigation, it is found that at Reynolds number 9500, the overall heat transfer coefficient is enhanced by 15% and pressure drop enhanced by 15% compared with water at 6500 Reynolds number and friction factor is enhanced by 16% compared with water at 0.6% Multi-Walled Carbon Nanotubes/water nanofluids concentration.