天然气管道线路截断阀误关断判断算法

为减少天然气长输管道线路截断阀误关断次数,提高阀室泄漏检测系统的可靠性,基于大量阀室误关断事件的原因分析,结合气体流体力学理论,运用SPS仿真软件建立了长输天然气管道泄漏仿真模型。探究了天然气长输管道泄漏过程中泄漏位置、管道运行压力等条件对压力下降过程的影响规律,并在此基础上计算在特定管道出现泄漏时可能发生的最快压力下降过程数据。据此,设计了一种天然气管道线路截断阀误关断判断算法,并编写了管道泄漏线路截断阀关断的控制程序。仿真数据及试验结果表明,该方法可根据压力变化特征实现误关断信号与真实泄漏信号的判断,降低系统误关断率。

Judgment algorithm for false shutoff of block valve in natural gas pipeline

In order to reduce the frequency of false shutoff of the block valve in a long-distance gas pipeline and improve the reliability of the leakage detection system in a valve chamber,the leakage simulation model of a long-distance gas pipeline was established with SPS simulation software by referring to the theory of gas fluid mechanics based on the analysis on causes of a large number of false shutoff events occurred in valve chambers.With this simulation model,the influence rules of the conditions including the leakage location and operating pressure of a pipeline on the process of pressure drop during the leakage of a long-distance gas pipeline was studied,and on that basis,the process data of the possible maximum pressure drop during the leakage of a pipeline was calculated.Then,a judgment algorithm for false shutoff of block valves in a natural gas pipeline was designed,and a control procedure was developed for shutoff of block valves in a leaked pipeline.The simulation data and experimental results show that with the method,the false shutoff signal and the real leakage signal can be distinguished according to the characteristics of pressure change,and the rate of false shutoff of the system could be reduced.