Convective Heat Transfer Enhancement Using Flow Divider Type Insert

Convective heat transfer enrichment represents an efficient technology for improving the performance of shell and tube heat exchangers. This technology finds application in various industrial sectors, including process industries, thermal power plants, heating, ventilation, and air conditioning systems, refrigeration systems, and automobile radiators. Techniques of Heat transfer enrichment encompass various methods used to improve the amount of heat transfer without compromising overall performance. These techniques are categorized as active, passive, and compound methods. The primary objective of this study is to investigate passive techniques for enhancing heat transfer. In this research, we employ a Flow Divider-type insert to boost heat transfer efficiency. Passive inserts disrupt the boundary layer, significantly enhancing heat transfer. These inserts transform laminar flow into turbulent flow. For this project, non-metallic inserts are utilized with air as the working medium, and various performance parameters are examined. While the insert improves the heat transfer rate, it also necessitates an increase in pumping power. Therefore, it is crucial to identify an insert that enhances the heat transfer rate with minimal additional pumping power. To assess this performance, we introduce an essential parameter known as the overall enhancement factor. This factor is the ratio of Nu/N
0
to f/f0, and it should be maximized for optimal performance. In this experiment, the insert measures 25mm × 25mm and is 3mm thick, composed of carbon fiber material. The findings reveal that as Reynolds number increases, the Nusselt number increases while the friction factor decreases. It is also observed that the maximum heat transfer occurs at the maximum Reynolds number (22392), reaching 113.9094 W, while the minimum heat transfer (58.94 W) is observed at the minimum Reynolds number (11404). The highest friction factor (0.339458) is observed at a Reynolds number of 11252.78, while the lowest friction factor (0.055317) is noted at a Reynolds number of 19990.2457. These results underscore the importance of optimizing Reynolds numbers to achieve the desired heat transfer and pumping power balance.