|
Abstract
|
Heat exchangers are very important in many varied industrial applications, including power generation, chemical processing, refrigeration, and automotive systems, since they enable effective heat transfer between two or more fluids, assuring maximum utilization of energy and stability in operations. Multi-channel heat exchangers are now coming into prominence due to their compact design and high thermal performance, which makes them well suited to applications where space and efficiency are key. In the present work, different turbulence models are comparatively evaluated for multi-channel heat exchangers. The aim is to identify the most appropriate model capable of capturing the complex phenomena of flow and heat transfer in such systems by comparing their performance and predictive capabilities. Due to the variations among turbulence models, namely k-ε RNG, k-ε Standard, k-ω SST, and k-ω Standard, differences in Nusselt numbers were observed within the Reynolds number range of 5,000 to 10,000. The highest Nusselt number, 130.40, was recorded at Re = 10,000 for the k-ε RNG model. This value shows a deviation of 39.164%, 32.63%, and 37.23% compared to the k-ε Standard, k-ω SST, and k-ω Standard models, respectively. Similarly, variations in the friction factor were observed across the Reynolds number range of 5,000 to 10,000, mirroring the trends seen in the Nusselt number. The highest friction factor, 0.1857, was recorded for the k-ε RNG model at Re = 5,000. This value differs by 7.86%, 1.71%, and 3.6% compared to the k-ε Standard, k-ω SST, and k-ω Standard models, respectively.
|