输气管线负压波法最小可检测泄漏量的研究

A Study of Smallest Detectable Leakage Flow Rate Based on Negative Pressure Wave Method for Gas Pipelines

基于输气管线的物理模型,结合负压波幅值沿管线近似指数衰减的机理提出了一种用于评估输气管线泄漏监测与定位系统性能的指标--最小可检测泄漏量的方法,同时也推导出了输气管线敏感点的数学表达式。通过实际数据仿真分析了管线的负压波衰减因数、泄漏点、仪器精度与噪声等对最小可检测泄漏量与敏感点的影响,其结果为泄漏检测与定位系统的性能指标,如灵敏度、评估能力等给出了理论指导,使得以前只能定性分析的问题,可以定量进行研究。

Based on the physical model of gas pipeline, mathematical description for the amplitude change of Negative Pressure Wave（NPW） and its attenuation traveling along the pipeline have been deduced. On the basis of above description, the methods for evaluating Smallest Detectable Leakage Flow Rate（SDLFR） and determining the sensitive point of the gas pipeline have been proposed. The simulations show the influences of such factors as attenuation factor,leakage position, pressures at inlet and outlet, precision of the instruments and noise and so on SDLFR and sensitive point. And the results are of significance to evaluate the performance of the leak detection and location systems based on NPW method. It makes the problems changed from qualitative analysis to quantitative researeh now.