海底输气管道泄漏点压力变化特性的模拟研究

Simulation Study on the Pressure Change Characteristics of the Leakage Point in Submarine Gas Transmission Pipelines

为了研究海底输气管道发生泄漏时压力信号的传播特点,利用Pipeline studio模拟软件进行了海底输气管道和陆地输气管道在相同输气压力和泄漏孔径下发生泄漏时泄漏点压力信号变化的对比,同时进行了海底输气管道在不同工况下泄漏点压力变化特性的模拟研究。结果表明:输气压力和泄漏孔径一定时,外界压力越大,泄漏点压力衰减后越快速趋于稳定,且稳定时压力越小;输气压力一定时,一定范围内,泄漏孔径越大,泄漏点压降速率越大,衰减后达到稳定所需时间越长,稳定时压力越小;输气压力超过一定范围则相反,且泄漏孔径过大会造成泄漏点压力无规则波动。泄漏孔径与管径的比值大小对泄漏点压力衰减后达到稳定时所需要的时间以及稳定后的压力具有重要影响,根据其比值可以大致确定压力传感器的最佳安装间距,这对于提高海底管道检测准确度和降低检测成本具有一定的借鉴意义。

In order to study the propagation characteristics of the pressure signal when the submarine gas pipeline leaks, Pipeline studio simulation software is used to compare the pressure signal change of the leakage point when the submarine gas pipeline and the onshore gas pipeline leak under the same gas pressure and the same leakage aperture. At the same time, the simulation study on the pressure change characteristics of the submarine gas pipeline under different working conditions is carried out. The result shows that when the gas transmission pressure and the leakage aperture are fixed, the larger external pressure is, the more stable the pressure of the leakage point tends to be after attenuation, and the smaller the pressure is at steady state. When the gas transmission pressure is constant, within a certain range the larger the leakage aperture is, the greater the pressure drop rate at the leak point is, the longer the time required for stabilization after attenuation, and the smaller the pressure is at steady state. The condition will be the opposite when the pressure exceeds a certain range, and the excessive leakage aperture will make the pressure at the leak point fluctuate irregularly. At the same time, the ratio of the leakage aperture to the diameter of the pipe has an important influence on the time required for the pressure at the leakage point to be stabilized and the pressure after stabilization,and the optimal installation distance of the pressure sensor can be roughly determined according to the ratio, thereby is of significance in improving detection accuracy and reducing cost for submarine pipelines.