Effect of tube thickness on heat transfer performance in a shell and tube heat exchanger

This study investigates the effect of tube-thickness variation on the heat-transfer performance of a shell-and-tube heat exchanger designed for high-purity oxygen production with a capacity of 30 tons per day. The design was conducted in accordance with TEMA and ASME Section VIII Division II standards. A computational fluid dynamics (CFD) approach was implemented using SimScale to simulate heat transfer effectiveness across tube thickness variations ranging from 0.5 mm to 1.5 mm. All other geometric and operating parameters were held constant to isolate the wall-thickness effect, and effectiveness (ε) was computed from CFD outlet temperatures using the standard Q/Q max definition under steady conjugate heat-transfer conditions. Results showed a significant inverse relationship between tube thickness and heat exchanger effectiveness. The maximum effectiveness was 0.969 for a tube thickness of 0.5 mm, while the lowest was 0.931 at 1.5 mm. A verification protocol comprising mesh refinement and global energy-balance checks was conducted to ensure numerical consistency, and CFD predictions were benchmarked against an analytical ε–NTU hand calculation, yielding a maximum deviation of less than 5%. These findings highlight the importance of optimizing tube geometry to enhance thermal performance in industrial heat exchanger applications. In practice, the thermal gains from thinner tubes must be balanced with ASME/TEMA minimum-thickness and mechanical-integrity constraints, providing an isolated and actionable quantification of wall thickness impact for industrial STHE design.