Heat exchange equipment plays a vital role in the chemical and energy industries; corrosion failure of this equipment causes serious economic losses and potential security threats. Heat transfer affects corrosion behaviour, and promotes the formation of a concentration gradient in a temperature field. However, the concentration changes in corrosive media are often ignored, especially in convective heat transfer environments. In this study, based on thermal diffusion theory, we focus on the concentration distributions of the corrosive media, concentration changes at the solid‒liquid interface and time for the concentration to stabilize under static and laminar heat transfer conditions. The results show that for NaCl and H2SO4 solutions, positive heat transfer decreases, negative heat transfer increases, and corrosive media concentration changes at the interface. The interface concentration changes of H2SO4 reach 26% (considering error: 20% ∼ 31%) and 30% (considering error: 24% ∼ 36%) under static and laminar heat transfer conditions with temperature differences of 50 °C, respectively. In addition, during laminar heat transfer, the concentration distribution undergoing thermal diffusion is jointly determined by the temperature difference and flow rate; the concentration stabilization time is determined by the temperature boundary layer thickness. These results indicate that the actual corrosive media concentrations at the heat transfer interface are not equivalent to the bulk phase concentration in the corrosion solution; the influence of heat transfer on the metal corrosion behaviour cannot be ignored. This study provides a new perspective for metal corrosion and protection in heat transfer environments.
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