Performance Evaluation and Structure Optimization of a New Type of Shell-and-Tube Heat Exchanger with Embedded Louver Segmental Baffle Support

Noticing the low efficiency caused by fluid flow retention phenomena and the high pressure loss in the shell-and-tube heat exchanger with common segmental baffle, an embedded louver shell-and-tube heat exchanger is designed, and numerical simulation of fluid heat transfer and flow characteristics of this novel heat exchanger is carried out. Results reflect that the structure with embedded louvers can significantly reduce the area of the flow retention zone and increase the fluid disturbance on the leeward side of the baffle, making the pressure drop of the shell side fluid 20.5–21.3% lower and the heat transfer coefficient 8.75–16.4% higher. At the shell side fluid inlet, outlet, and middle section of the heat exchanger, the average fluid temperatures are 0.34 °C, 2.12 °C, and 3.08 °C higher, respectively, compared to those in the common segmental baffle shell-and-tube heat exchanger. On this basis, the influence of the louver geometrical parameters, including louver angle and louver length, on the performance is also analyzed. The comprehensive evaluation factor is proposed and applied to evaluate the improvement of heat exchangers with different design parameters. The results showed that the evaluation factor is higher when the louver angle is 60°. However, when the louver length increases from 1/7 to 1/3 of the distance between adjacent baffles, the evaluation factor is almost unchanged.