高压CO^(2)管道泄漏的瞬态行为数值研究  

Numerical study on the transient behavior of high-pressure CO_(2) pipeline leakage

作　　者：鲁寨军[1,2,3] 严利果 肖程欢 姚术健 LU Zhai-jun;YAN Li-guo;XIAO Cheng-huan;YAO Shu-jian(Key Laboratory of Traffic Safety on Track,Central South University,Ministry of Education,Changsha 410075,China;Joint International Research Laboratory of Key Technology for Rail Traffic Safety,Changsha 410075,China;National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle,Changsha 410075,China)

机构地区：[1]轨道交通安全教育部重点实验室,长沙410075 [2]轨道交通安全关键技术国际合作联合实验室,长沙410075 [3]轨道交通列车安全保障技术国家地方联合工程研究中心,长沙410075

出　　处：《安全与环境学报》2021年第2期758-763,共6页Journal of Safety and Environment

摘　　要：作为碳捕捉与封存(CCS)技术中重要的一环,高压CO2管道运输过程中极有可能发生破裂事故,导致CO_(2)的大规模泄漏,进而对周围造成一定的危害。针对CO_(2)管道泄漏的瞬态过程准确预测问题,利用用户自定义函数(UDF)和用户自定义真实气体模型(UDRGM),将Span-Wagner状态方程和Lee相变模型嵌入Fluent求解器中,建立了非平衡相变数值模型。并通过与相关试验数据进行对比分析验证了该模型的准确性。在此基础上,进一步分析了小尺度泄漏模型的瞬态行为。结果表明:泄漏发生后形成的两相流加速膨胀形成马赫盘结构;出口质量流量迅速上升到32.5 kg/s,然后慢慢增加到35 kg/s左右,随后保持稳定;射流区域的温度低于环境温度,在10 ms内的最低温度接近254 K。In this paper,a non-equilibrium phase transition numerical model based on the mixture multiphase model was established to simulate the near-field jet of high-pressure CO_(2)pipeline leakage.To model the phase transition process accurately,the Span-Wagner equation of state(SW Eo S)and Lee model were successfully embedded into the Fluent solver by using the User Defined Real Gas Model(UDRGM)and User Defined Function(UDF),respectively.By contrast,the values and changing trends of monitoring pressure by simulation were found to be highly consistent with the test results for both small-scale and large-scale CO_(2)pipeline leakage,which verified the accuracy of the numerical model.On this basis,we further analyzed the transient behavior of CO_(2)in the near-field jet of small-scale CO_(2)pipeline leakage and the change of mass-flow rate at the leakage opening,as well as the velocity contours and temperature contours of the near-field jet at the flow time of 1 ms,5 ms,8 ms,and 10 ms after leakage.The results show that the high-pressure CO2 ejected from the leakage opening at a high speed is because of the huge pressure difference between the inside and outside of the pipeline,continuously undergoing phase transition and expansion,and finally forming a highly under-expanded jet flow.According to the variation trend of the mass-flow rate at the leakage opening,the leaking process could be divided into a rapid growth stage,a transitional growth stage,and a stable stage.In the rapid growth stage,the mass-flow rate increases rapidly to a value of32.5 kg/s after leakage.In the transitional growth stage,the growth rate of the mass-flow slows down and then gradually raises to about 35 kg/s.And in the stable stage,the mass-flow rate remains stable.Mainly affected by the Joule-Thomson effect and heat transfer during the phase transition,the temperature of the jet flow is lower than the ambient temperature,and the lowest value.

关 键 词：安全工程 二氧化碳 管道泄漏 非平衡相变 数值仿真 二次开发 

分 类 号：X937[环境科学与工程—安全科学]