Entropy generation of ferronanofluid flow in industrially designed bended dimpled tube

Abstract

In this study, numerical analyses were conducted on bended tube with different bending radius and pitch ratios of dimpled fin under different Dean numbers from 9.1 to 301.2. The study examined in bended tube containing three dimple pitch ratios (P/d = 6.0–7.5–9.0) carried out under uniform heat flux of 600 W/m2 and different nanofluid volume fractions of Fe3O4/H2O (0.0 ≤ φ ≤ 2.0 %). The thermo-hydraulic performance and entropy generation of bended tubes were investigated. The results showed that Case 10 provided the highest Nu using H2O compared to Case 16, this enhancement was realized as 17.56 %. When nanofluid was used, the highest Nu was obtained at φ = 2.0 % volume fraction in Case 7 by 24.47 % in comparison with non-DT at Dn = 245.9. The highest PEC value of Case 7 using φ = 2.0 % was monitored as 1.11 at Dn = 245.9. Compared to the frictional and total EnGs of P/d = 6.0 and 9.0, the frictional and total EnGs of P/d = 6.0 show a decrease of 10.05 % and 9.60 %, respectively.