基于反应输运耦合机理的腐蚀演化研究  

Corrosion evolution based on reaction transport coupling mechanism

作　　者：王凯[1] 艾琦 卢金玲[1] 张巧玲[1] 王跃社[2] WANG Kai;AI Qi;LU Jinling;ZHANG Qiaoling;WANG Yueshe(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi'an University of Technology,710048 Xi'an,China;State Key Laboratory of Multiphase Flow in Power Engineering,Xi'an Jiaotong University,710049 Xi'an,China)

机构地区：[1]西安理工大学西北旱区生态水利国家重点实验室,西安710048 [2]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《应用力学学报》2022年第5期887-894,共8页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金资助项目(No.51906200);陕西省教育厅重点实验室资助项目(No.19JS045);陕西省教育厅协同中心资助项目(No.20JY044)。

摘　　要：油气管道输运介质中化学反应、离子传质、金属溶解之间存在着复杂的交互作用,极易诱发浓度场-电势场耦合作用下的腐蚀问题。本研究综合考虑溶液化学反应、界面电化学反应、离子扩散和电迁移等多种不同时空尺度的物理化学过程,基于电场、浓度场的耦合机理建立腐蚀演化动力学模型,分析了浓度分布规律、腐蚀电流密度分布规律、腐蚀形貌演变规律等动态腐蚀行为,进而探究了局部化学环境以及电化学行为的耦合过程对腐蚀生长动力学的作用机制。研究发现腐蚀演变规律由电学作用和化学作用之间的竞争作用决定,随着时间的推移,电学作用占据主导地位,导致腐蚀电流密度逐渐减小,蚀坑形貌的演变始终保持对称性,而腐蚀坑宽度的增长小于深度的增长。In the transportation medium of oil-gas pipelines,there exist complex interactions among chemical reactions,ion mass transfer and metal dissolution,which can easily induce corrosion under the coupling effect of concentration field and electric potential field.This paper comprehensively incorporates various physical and chemical processes at different time and space scales,including solution chemical reactions,interface electrochemical reactions,ion diffusion and electromigration.Based on the coupling mechanism of electric field and concentration field,a corrosion evolution kinetic model is established.The dynamic corrosion behaviors including concentration distribution,corrosion current density and corrosion morphology are analyzed.The mechanism of the coupling process of local chemical environment and electrochemical behavior on corrosion growth kinetics is explored.This study found that the law of corrosion evolution is determined by the competition between electrical and chemical effects.As time proceeds,electrical effects dominate the corrosion process,resulting in a gradual decrease in corrosion current density.The evolution of pit morphology always maintains symmetry.The increase in the width of the corrosion pit is less than the increase in the depth.

关 键 词：多场耦合 腐蚀 动力学模型 离子传质 演化规律 

分 类 号：TK17[动力工程及工程热物理—热能工程]