LAUSR

Abstract It is still high on the agenda for the highly-effective utilization of exhaust flue gas in the condensing-type heat exchangers employing with anti-corrosive surface modification. In this paper, we carried out the wettability and condensation heat transfer characteristics of vapor-containing flue gas outside three kinds of anti-corrosive coated finned tubes. The influence of Re (160 ~ 200) and Ja (0.8 ~ 2.9) of flue gas, and coating layers (Ni-P composite plating, organic coating, Ni-P composite plating + organic coating) on condensation heat transfer were also investigated. The results showed that the contact angle hysteresis is affected by the surface roughness and surface tension. The coating layers all exhibited four condensation periods of water vapor. The combining coating layer (Ni-P composite plating + organic coating) has the most excellent heat-transfer performance. Additionally, a dimensionless formula was established among Nu, Re and Ja for different coating layers. The dimensionless criterion can be helpful for the heat and mass transfer characteristics of vapor-containing flue gas and design the similar surface-modified condensation heat exchangers.