输气管道泄漏速率模型研究进展
Progress of research on leakage rate model of gas pipeline
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摘要: 泄漏量是输气管道泄漏事故后果评价的重要依据。管道泄漏事故发生后, 从泄漏处向管道的上下游传递减压波, 管道内外巨大的压力差会产生焦耳-汤姆逊效应令气体温度下降, 使气体中的重组分冷凝析出, 而流量系数的不断变化导致管道内的流场计算更为困难。通过调研现有的输气管道泄漏速率模型, 总结了目前泄漏速率模型的研究进展, 并分析了各模型的局限性。管道泄漏速率模型多基于计算流体力学建立, 其计算精度优于传统模型, 但并不能耦合管道全线的水热力参数变化实时计算泄漏速率, 因此开发可用于求解长距离输气管道泄漏模型的算法是未来重要的研究方向。Abstract: Leakage amount is an important basis for consequence assessment of gas pipeline leakage accident.Once the pipeline leakage accident occurs, the negative pressure wave will be transmitted from the leakage place to the upstream and downstream of the pipeline.The huge pressure difference inside and outside the pipeline will induce the JouleThomson effect, which may lower the temperature of the gas, condense and separate out the heavy components in the gas.However, the dynamic flow cofficient makes it even harder to calculate the flow field inside the pipeline.By investigating the existing leakage rate models of gas pipelines, the research progress of current leakage rate models was summarized and the limitations of each model were analyzed.Most of the pipeline leakage rate models are based on computational fluid dynamics with better computational accuracy than traditional models.However, the leakage rate in real time cannot be calculated by coupling the changes of hydro-thermal parameters across the pipeline.Therefore, the development of algorithms used to solve the leakage model of long-distance gas pipelines will be an important research direction in the future.