CFD Analysis of Different Baffles in Shell and Tube Exchanger
Keywords:
Shell-and-tube heat exchanger, baffle design, pressure drop, heat transfer, computational fluid dynamicAbstract
Shell and tube heat exchangers are among the most common equipment in industrial processes because of their heat exchange efficiency. However, designing these heat exchangers to enhance their performance can be cumbersome and time-consuming. This study focuses on evaluating the performance of shell and tube heat exchangers with different numbers of baffles placed inside the shell, and identifying the most suitable turbulence model. In this study, the flow characteristics inside the heat exchangers were modelled using three turbulence models: Spalart-Allmaras, k-ε standard, and k-ε realisable models. The simulations were performed with the number of baffles ranging from one to seven to understand their effect on heat transfer and pressure drop. When the number of baffles in the heat exchanger increases, the pressure drop across the heat exchanger also increases. Model D exhibited maximum pressure distribution, which occurred with 12 baffles. The velocity streamlines from the experiment showed that a higher number of baffles led to an increase in flow. This study also aimed to compare three turbulence models, and the results indicated that the k-ε realisable model performed the best of the three models. This study also highlights the importance of designing a shell and tube heat exchanger with an appropriate number of baffles. Although more baffling is advantageous for heat transfer, it also results in a higher pressure drop. In summary, as evidenced by the results presented in this paper, the baffle design is crucial for heat exchangers.