Thermal performance enhancement of compact heat exchangers: Investigating the influence of coil orientation and curvature radius

This research addresses the critical need for high-efficiency thermal management by determining the optimal geometric configuration for curved coiled heat exchangers. Through a comprehensive two-stage analysis using computational fluid dynamics, this study fills a significant research gap by evaluating the transition from vertical to horizontal orientations in compact systems. The initial phase compared a simple heat exchanger, a vertical curved coil, and a horizontal curved coil, identifying the horizontal configuration as superior due to its ability to optimize the generation of Dean vortices. In the second phase, geometric optimization was performed on four horizontal models with curvature radii ranging from 15 mm to 30 mm. The results demonstrate that the model with a 30 mm radius provides the highest thermal efficiency. At a Reynolds number of 2000, the heat transfer coefficient for this optimal model improved by 36.7% compared to the simple heat exchanger. Furthermore, the thermal performance criterion analysis confirmed that the 30 mm radius configuration achieved an ultimate efficiency improvement of 200% over the baseline model. These findings offer a precise and cost-effective geometric guideline for developing next-generation compact heat exchangers, aiming to reduce operational energy consumption in chemical processing and climate control industries.