LAUSR

This study investigates the impact of cathodic protection design on the corrosion resistance of heat exchangers (HE#1, HE#2). Two distinct heat exchanger assemblies underwent a 720-hour cyclic corrosion test, revealing higher corrosion resistance in HE#2 compared to HE#1. The difference in cathodic protection design was observed at the fin-tube junction, where variations in the filler metal composition played a crucial role. Corrosion resistance was primarily influenced by the cathodic protection design at this junction rather than by the header-tube junction or the inherent corrosion susceptibility of the tube. Boundary element method simulations quantitatively confirmed that the tube's corrosion resistance was supported by the current provided at the fin-tube junction, particularly across the fin-free zone. Optimization of the cathodic protection design was achieved by adjusting the Zn content in the filler metal at the fin-tube junction. These findings provide valuable insights for enhancing corrosion resistance in practical heat exchanger applications.