Enhanced heat transfer in wavy channels with vortex generators: A CFD investigation

Abstract

The corrugated channel is a widely used method for enhancing heat transfer and has been employed in many thermal engineering applications, such as heat exchangers and compact cooling systems. The corrugated sections create recirculation zones, which can impact flow efficiency. For that reason, we introduced vortex generators. In this study, numerical investigations were conducted on convective heat transfer in a wavy corrugated channel within a Reynolds number ($Re$) range of 500–5000. The wavy channel was equipped with two types of vortex generators (VGs) in this configuration, presenting a novel setup not previously addressed in existing studies: full-circle vortex generators (FCVGs) with different diameters (D = 2, 4, and 6 mm), and two-half-circle vortex generators (THCVGs) with variable distances between the halves (S = 1, 2, and 3 mm). The numerical simulations were performed using the finite volume method in ANSYS Fluent, with the SST $k$–$\omega$ turbulence model employed for high Reynolds number flows. The VGs generally improve heat transfer. Performance is measured using the pressure drop ratio ($PR$) and the percentage enhancement ($PE$). To evaluate thermo-hydraulic performance, the Performance Factor (PF) was also calculated, showing that the FCVG configuration (D = 6 mm) achieved the best balance in laminar flow with a maximum PF of 0.94 at $Re=500$, while smaller FCVGs performed better in the turbulent regime compared to THCVGs. FCVGs (D = 6 mm) had the largest $PE$, increasing by 46% at $Re=1000$, whereas THCVGs (S = 1 mm) increased by 38% at $Re=500$. However, because $PR$ values can rise more for FCVGs than for THCVGs, this enhancement comes at a pressure drop cost. Such improvements enable more compact and efficient heat exchanger designs, supporting energy savings and system miniaturization.