基于元胞自动机的金属土壤腐蚀行为及产物层模拟研究

Simulation of Metallic Soil Corrosion Behavior and Corrosion Product Layer Based on Cellular Automata

油气输送管道多敷设于地下,管道金属与土壤接触极易引发腐蚀问题。为解决该问题,运用元胞自动机方法构建了一种综合考虑了土壤含水量、含氧量和电阻率等关键影响因素的金属土壤腐蚀动力学模型,并利用该模型模拟了不同土壤含水量(C)、腐蚀溶解概率(P_(w))及扩散概率(P_(d))条件下的土壤腐蚀行为。结果表明:随着土壤含水量增加,金属土壤腐蚀速率呈先增加再减小的趋势,且最高腐蚀速率相对应的临界含水量(C_(t))随扩散概率(P_(d))增大而减小,说明水和氧气的扩散对腐蚀速率起主要控制作用,这与实际土壤腐蚀过程相一致,表明所提出的模型能够较为准确地模拟土壤腐蚀行为.

As the oil and gas pipelines are mostly laid underground,the pipeline metals are easy to be corroded due to its contact with the soil.For solving this problem,the cellular automata method was applied to construct a dynamic model of metallic soil corrosion,which took into account the key influencing factors such as soil water content,oxygen content and resistivity.With the help of this model,the soil corrosion behavior was simulated for the conditions with different water contents(C),corrosion dissolution probabilities(P_(w))and diffusion probabilities(P_(d)).Results showed that with the increase of soil moisture,the metallic soil corrosion rate increased first and then decreased.With the increase of diffusion probability(P_(d)),the critical water content corresponding to the highest corrosion rate(C_(t))decreased,indicating that the diffusion of water and oxygen dominated the corrosion rate.This was consistent with the actual process of soil corrosion,so it proved that the proposed model could provide a relatively accurate simulation of the soil corrosion behavior.