Investigation of the Working Mechanism of CO₂–H₂O Flow Corrosion of Mild Carbon Steel

Abstract

In this work, the working mechanism of the CO 2 − H 2 O flow corrosion of mild carbon steel is investigated by a twodimensional simulation. Three models including a mass transfer model, an electrochemical model, and a convection−diffusion model are integrated to study the comprehensive working mechanisms. Several factors including temperature, pH, CO 2 partial pressure, and flow velocity are considered. The results show that the flow corrosion increases with increasing temperature, decreasing pH or increasing CO 2 partial pressure. As the temperature reaches above 60 °C, H 2 O reduction of the cathode becomes significant in the CO 2 −H 2 O flow corrosion. The cathode reaction of the corrosion at low pH is dominated by H + reduction and sensitive to flow velocity, while with the increase of pH, H 2 CO 3 plays an obvious buffer role to supplement H + . The effect of the flow velocity on CO 2 −H 2 O flow corrosion increases with the temperature, where the flow turbulence is found to play an important role in promoting corrosion enhancement.

Multiscale Modeling and Artificial Intelligence for Multiphase Flow Science

“…Pan et al applied 2D graphene membranes for alcohol/water separation and proposed a theoretical framework that explains interfacial adsorption effects on fluid transfer in nanochannels. Fang et al explored the CO 2 –H 2 O flow corrosion of mild carbon steel with a two-dimensional simulation, emphasizing the impact of temperature, pH, CO 2 partial pressure, and flow velocity on corrosion rates. Wang et al simulated the migration of a sessile droplet on a substrate with a temperature gradient, revealing how factors such as contact angle and viscosity ratio influence droplet migration speed and direction.…”