Effect of a novel turbulator on thermohydraulics and exergy efficiency of a heat exchanger contains SWCNT-SiO2/water: A numerical study

Abstract

This study uses the finite volume method (FVM) to examine the effect of a twisted turbulator (TT) on the thermo-hydraulic performance (THP) of a dual-tube heat exchanger (HE) contains two-phase (TP) SWCNT-SiO2/water hybrid nanofluid (HNF). Numerical simulation of the HE with the TT and HNF flow is done using the Eulerian model. Also, the second-order upwind method is employed for the discretization of the equations and their convergence. The study has been done for Reynolds numbers (Re) of 6000 to 24000 and volume concentration (VC) of 0 to 4% of nanoparticles. The results obtained from this study show that the average Nusselt number (Nuave) and pressure drop (Δp) in the dual-tube HE assembled with TT are extensive with Re and volume concentration (VC). When VC = 4% and Re = 24000, putting the TT Case 4 intrant the HE leads to an enhancement in the amounts of Nuave and Δp by 91.34% and 252.19%, respectively, in comparison to the HE in absence of TT. The results demonstrate that the use of TT is desirable for 6000 < Re < 24000 and 1% < VC < 4%. For the HE with a TT Case 4, the exergy efficiency ηex value then it gets better 35.66% when VC = 4% and Re = 24000.