Abstract: Flow-Accelerated Corrosion（FAC） is a phenomenon that induces carbon steel to degrade, which usually occurs in the secondary pipes in nuclear power plant. Many accidents have happened because of FAC in many countries in the word. A computational model for FAC of the carbon steel in single flows is developed with reasonable assumptions. The solubility of Fe₃O₄ in high temperature is calculated. Mass transfer coefficients are calculated with method of CFD（Computational Fluid Dynamics）, and the results are successfully used in the computational model. FAC rate in straight pipe predicted by the model agrees with results in experiment. The results show that FAC is influenced by temperature, pH and velocity greatly, which is very significant in preventing FAC-induced accidents from happening.