Comparative study of shell-and-tube heat exchanger designs for improved thermal performance and energy efficiency

Heat exchangers are fundamental components in numerous industrial processes. This study presents a new shell-and-tube heat exchanger (STHX) design that significantly improves cooling efficiency. The proposed design, featuring a double shell, elliptical tubes at a 90° angle of attack, and flower baffles (DSTHX-90°-F), achieves a 121% increase in temperature drop in the shell side relative to conventional heat exchangers. A computational analysis was performed using ANSYS-Fluent 2021-R2. The numerical model was validated against experimental data from both a conventional single-shell configuration and a prototype of the novel double-shell design, confirming the model’s reliability across different geometries. The investigation was conducted in three stages. initially, a comparative analysis was conducted on a heat exchanger with a 25% baffle cut-off, examining circular (STHX-C-S), elliptical tubes at 90° (STHX-90°-S), and 0° (STHX-0°-S) angles of attack. The elliptical tube at 90° demonstrated the greatest temperature reduction in the shell zone. In the second stage, incorporating flower baffles with elliptical tubes at 90° (STHX-90°-F) resulted in a 69% reduction in pressure drop compared to STHX-90°-S. The third stage developed the DSTHX-90°-F design, combining the double shell, elliptical tubes, and flower baffles for superior performance. This study provides comprehensive flow visualizations using temperature contours, streamlines, and velocity distributions, illustrating substantial enhancements in heat exchanger performance.