A Numerical Study of BeO-CuO Hybrid NF with Twisted Tape on Tubular Heat Exchanger to Determine Heat Transfer Performance

A numerical investigation was performed on the effect of BeO-CuO hybrid nanofluid (NF) with simple twisted tape (TT) on tubular heat exchanger (HE) to determine heat transfer performance of the tubular HE. The ratio of BeO-CuO nanoparticles (20:80) was mixed in the W/EG in the 60:40 ratio to prepare the hybrid NF. The experiments were performed using hybrid NF with inclusion of TTs for fully developed flow in the turbulent regime with Re range of 2900–11,200 with constant flux of 7957 W/m2. Experimental data from published works has been used to validate 3-D simulations. The equations have been solved by using the RNG k-ε model and finite volume approach. The both doping of NPs and inclusion of TT inserts in the base fluids results in improved heat transfer performance. Overall, for Re of 2900 and higher Re of 11,200, the combination of Nanofluid and Plain Twisted Tape increases the Nusselt number by 118.159% and 65.58%, respectively. The friction penalty for combining hybrid NF with TT grows as Nu increases; for the lowest and greatest Re, this was reported to be 3.868 and 2.27 times greater than for plain tube (PT). The highest thermal performance factor (TPF) during the investigation was recorded as 1.15 for hybrid NF with TT insert at lowest Reynolds number.