电偶腐蚀数值模型的边界条件优化研究

Optimization of boundary conditions for numerical model of galvanic corrosion

提出了一种新颖的极化曲面边界条件设置方式,实现了腐蚀微环境实时变化对腐蚀动态影响的全过程数值模拟。考虑到AE44镁合金/Q235碳钢电偶对阴极为析氢反应,腐蚀环境主要涉及到的因素是溶液pH的变化,因此,研究了pH对电位-电流极化曲线的影响。通过建立模型系统研究了不同边界条件设置对模拟结果的影响,结果表明,当模型边界条件中考虑溶液pH的变化时,模拟结果最接近实验真实值,此模型模拟的精确度最大为94.10%,高于Tafel方程边界的54.87%和极化曲线边界的89.97%。

A novel polarized surface boundary condition setting method is proposed to achieve the full process numerical simulation of the impact of real-time corrosion microenvironment changes on corrosion dynamics.Considering the hydrogen evolution reaction between AE44 magnesium alloy/Q235 carbon steel galvanic couple and cathode,the main factor involved in the corrosion environment is the change in solution pH.Therefore,the effect of pH on the potential-current polarization curve is studied.The influence of different boundary condition settings on simulation results is evaluated through establishing a model system.The results indicate that the simulation results approach the actual experimental values when considering the changes of solution pH in the model boundary conditions.The maximum accuracy of this model simulation is 94.10%,which is higher than 54.87%of the Tafel equation boundary and 89.97%of the polarization curve boundary.