Heat Transfer Enhancements of Low Volume Concentration CNT/Water Nanofluid and Wire Coil Inserts in a Circular Tube

Present study reports fully developed laminar flow convective heat transfer and friction factor characteristics of MWCNT/water nanofluid (φ=0.15%) flowing through a uniformly heated horizontal tube with and without wire coil The stable nanofluid was prepared by dispersing CNTs of diameter 10 nm in distilled water. The experiments using the plain tube and with wire coil inserts were also carried out with distilled water as the working fluid for experimental setup validation and comparison. The experimental results reveal that the use of nanofluids increases the heat transfer rate with negligible increase in friction factor in the plain tube and the tube fitted with wire coil inserts.