Synergistic effects of wavy fin geometry and tube profile on thermal-hydraulic performance of finned-tube heat exchangers: a multi-objective optimization analysis

In response to the global sustainable development strategy, improving energy efficiency has become a key task in the industrial sector. Fin-and-tube heat exchangers are widely used in various energy conversion settings, and their performance directly affects overall energy consumption. Therefore, researching ways to optimize these devices is highly valuable. This study focuses on a sinusoidal wave finned-tube heat exchanger, selecting amplitude (A), number of corrugations (N), and the main shaft length (L) that determines the tube type as structural variables. Combining computational fluid dynamics, response surface methodology, and the NSGA-II algorithm, and using the Nusselt number ( Nu ), friction factor ( f ), and overall performance factor ( PEC ) as optimization targets, a Pareto front solution set is generated. Then the TOPSIS method is used to identify the most ideal solution based on the relative closeness. Results show that compared to other candidate solutions, the optimal solution boosts Nu by 10.18%, increases f by only 5.35%, and raises PEC by 8.01%, achieving a good balance between enhancing heat transfer and controlling flow resistance, which verifies the effectiveness of this optimization approach.