Thermal-hydraulic performance and design parameters in a curved-corrugated channel with L-shaped baffles and nanofluid

High heat generation is seen as a major issue in most mechanical and manufacturing industries, carrying with huge sub-problems. One of the possible cooling techniques is the combination of two or more passive methods, in particular for those parts with complex geometry. In this study, flow structure and heat transfer characteristics of the novel channel namely: curved-corrugated channel are numerically studied with using ZnO-water nanofluid and presence of L-shaped baffles. The influences of corrugations, baffles manner arrangement, and geometric parameters; corner angle (gamma= 30 degrees,45 degrees,60 degrees, and 90 degrees) and blockage ratio (BR=0.25,0.3. 0.35, and 0.4), at different Reynolds number (8000-32000) and volume fraction of ZnO particles (0-4%) are evaluated using thermalhydraulic performance method. The multi-phase mixture and the kappa-epsilon model are used to simulate turbulent nanofluid flows inside the curved-corrugated channels at constant temperature condition (T = 355 K). The results reveal that the formation of vortex flow and increased turbulence due to effects of corrugations and baffles can improve the heat transfer enhancement. Inline arrangement of baffle is superior to the staggered arrangement in thermal-hydraulic performance (PEC), and at lowest angle 30 degrees provide the best PEC. Regarding the friction ratio and compared to those of a plain channel, the effect of blockage ratio is considerable as it yields a multiplier impact of the corner angle. Reducing the blockage ratio and the corner angle, i.e. 0.25 and 30 degrees, yields to the best PEC at 1.99. New correlations for Nusselt number and friction factor for baffled curved-corrugated channel with using nanofluid are also reported.

Automated summary

The study investigates the flow structure and heat transfer characteristics of a novel curved-corrugated channel using ZnO-water nanofluid and L-shaped baffles. The results show that the effects of corrugations and baffles can enhance heat transfer by forming vortex flow and increased turbulence, with inline baffle arrangement outperforming the staggered arrangement, especially at a corner angle of 30 degrees.