高钢级输气管道裂纹延性扩展及止裂模拟技术研究

为了有助于我国高钢级管道止裂设计研究，使我国天然气管道运行更加安全，综合分析了气体载荷模拟方法和断裂处理方法，以及金属裂纹延性扩展与止裂预测之间的关系。以X90管线钢管为研究对象，基于ABAQUS软件，从天然气状态方程建立入手，研究建立全耦合的管道裂纹动态扩展及止裂数值模拟技术。将金属断裂准则应用于有限元计算中，通过流体、固体、断裂全耦合计算得到输气管道裂纹扩展时的裂纹扩展速度和气体减压波速度，对比两种速度判断裂纹是否可以止裂。

Research on Crack Ductility Expansion and Crack Prevention Simulation Technology of High Steel Grade Gas Pipeline

In order to promote the research on the crack arrest design of high-grade pipelines in China, and make the operation of natural gas pipelines more safe, the gas load simulation method and fracture treatment method, as well as the relationship between crack ductility expansion and crack arrest prediction are comprehensively analyzed. The high-grade X90 steel was studied based on the ABAQUS software. The numerical simulation technology of dynamic expansion and arrest of fully coupled pipeline cracks is established through the establishment of natural gas equation of equation. At the same time, the criterion of metal fracture was applied to the finite element calculation. The velocities of crack propagation and gas decompression wave of the gas delivery pipeline are obtained through the full coupling calculation of fluid, solid and fracture. At the same time, comparing the two velocities, it can be judged whether the crack is cracked.