阴极保护数值模拟计算边界条件的确定  

Determination of boundary conditions for cathodic protective numerical simulation

作　　者：郝宏娜[1] 李自力[1] 王太源[1] 丁延鹏[1] 衣华磊 

机构地区：[1]中国石油大学(华东)油气储运工程系,山东青岛266555 [2]中海油研究总院,北京100027

出　　处：《油气储运》2011年第7期504-507,472,共4页Oil & Gas Storage and Transportation

基　　金：国家重大专项"高含硫气田集输工艺与安全控制技术研究";2008ZX05017-04-01

摘　　要：数值模拟技术是求解阴极保护电位模型的有效方法,国内外流行的阴极保护数学模型包括分布型模型和时变型模型两种。在数值模拟过程中,边界条件的确定及其处理方式直接影响计算结果的准确性。为此,对国内外阴极保护数学模型的边界条件进行了分类,包括:边界电位已知的第一类边界条件(Dirichlet边界),电流密度已知的第二类边界条件(Neumann边界),以及边界电位和电流密度函数关系已知的第三类边界条件。系统阐述了阳极和阴极边界条件的确定方法以及非线性边界条件的处理方式,与Newton-Raphson迭代法相比,分段线性拟合法具有更好的灵活性和实用性,对于实测极化曲线的处理效果非常明显。指出在阴极边界条件方面,应加强对极化模型的研究。Numerical simulation method is an effective tool to calculate cathodic protection(CP)potential in practice.The currently used boundary conditions for this tool can be divided into two types:distribution model and time-dependent model.Boundary condition type and the corresponding processing method will have direct in? uences on results.Three type boundary conditions for CP simulation are reviewed:the f irst boundary condition or Dirichlet condition(with a known CP potential distribution),the second boundary condition or Neumann condition(with a known current density distribution) and the third boundary condition(with a known function relating CP potential and CP current density).The determination method for anodic and cathodic conditions and the processing method for nonlinear boundary condition are also discussed in detail.Results show that piecewise linear fitting is better than the Newton-Raphson fitting in flexibility and practicability,especially for polarization curve processing coming from lab measurement.More attention should be paid to the study of CP polarization model for a better CP boundary condition.

关 键 词：阴极保护 数值模拟 边界条件 极化 非线性 

分 类 号：TE88[石油与天然气工程—油气储运工程]