超临界CO2输运管道泄漏可能造成断裂扩展、人员伤害和介质释放等重大损失。为了防范泄漏风险，建立泄漏口径和位置、以及危险工况预测模型具有重要意义。泄漏特性研究是建立预测模型的重要基础，而目前对超临界CO2管道泄漏中压力和温度响应、状态参数变化等泄漏特性认识不够，有必要进行深入和精确研究。本项目拟基于工业规模管道(长258m，内径233mm)泄漏实验研究，结合理论分析和数值模拟，获得超临界CO2管道泄漏全过程压力和温度变化时空规律。阐析泄漏瞬间压力-温度突变耦合机理，分析减压波强度衰减规律，结合一维两相流模型来建立管道泄漏口径和位置预测方法。揭示泄漏后期管道长度和截面方向上压力、温度、密度等主要状态参量关联关系、以及干冰产生条件和流动规律，结合三维多相流CFD模拟来建立危险工况及部位预测模型。本项目研究对完善长输管道安全运行保障技术、预防泄漏可能引起的重大灾害具有重要科学意义和应用需求。

Leakages of supercritical CO2 conveying pipelines may cause significant losses such as pipeline fracture propagation, human injury and medium loss. In order to prevent pipeline leakage risk, it is especially important to establish the prediction model of the leakage orifice size and location and the dangerous condition. The study of leakage characteristic of supercritical CO2 pipeline is an important basis for establishing leakage prediction model. At present, there are insufficient understandings of the laws of the pressure and temperature responses and the state parameter changes during the leakage of supercritical CO2 pipeline, and it is necessary to carry out in-depth and accurate research. Based on the release experiments from an industrial scale pipeline (258 m long, 233 mm i.d.), combined with the theoretical analysis and the numerical simulation, to obtain the temporal and spatial variations of pressure and temperature in the whole process of the supercritical CO2 pipeline leakage. The coupling mechanisms of sudden changes of pressure and temperature at the moment of rupture will be analyzed. The attenuation law of decompression wave strength combined with the one-dimensional two-phase flow model will be researched for the establishment of the monitoring method of pipeline leakage orifice diameter and position. During the process of late leakage, the correlations of main state parameters such as pressure, temperature and density, and the formation condition and flow rule of dry ice particles will be analyzed. The prediction model of the hazardous condition and location combined with the three-dimensional multi-phase CFD model will be established. The research of this project has important scientific significance and application requirement for perfecting safe operation guarantee technology of long-distance pipeline and preventing major disasters caused by leakage.