新点蚀萌生和生长随机模型

A New Stochastic Model of Pitting Corrosion Initiation and Growth

对采用非齐次Poisson过程模拟点蚀萌生和采用非齐次Markov过程模拟点蚀生长的点蚀随机模型进行改进,针对已有研究中幂律模型和点蚀过程固定点蚀数目假定的不足,提出了一个新的点蚀生长插值模型,并将腐蚀过程中点蚀数目的动态变化纳入考虑,使数值模型更切合实际.与已有试验结果的对比表明:新插值模型不仅能避免幂律模型在物理上的不足,而且能更好地模拟铝合金和不锈钢实际的点蚀传播过程,对于点蚀瞬时萌生模型,插值模型模拟精度均高于幂率模型,因此该模型可作为最大点蚀深度生长随机过程的新模型,应用于油气输送系统.

The pitting corrosion stochastic model including non-homogeneous Poisson process used in pit generation and the non-homogeneous Markov process used in pit growth were improved.Aiming at the deficiency of both the existing power law model and the assumption of fixed number of pits during corrosion process,a new interpolation model for pitting growth was proposed,and the changes of number of pits during corrosion process taken into consideration.Comparison between the experimental and simulation results shows that the proposed model can not only avoid the deficiency of the power law model in physics,but also simulate the pitting corrosion propagation process of aluminum alloy and stainless steel more realistically.Besides,the interpolation model has higher accuracy than the power law model for pits initiated instantaneously.Therefore,the proposed model can be used as a new model for the stochastic process of maximum pitting growth,which can be used in oil and gas transportation system.