输气管道泄漏瞬态仿真分析

针对气体管道可能发生的泄漏工况,基于气体管道瞬变流动模型,结合泄漏边界条件,采用数值解法仿真得到泄漏后管道任一位置压力流量随时间的变化,并通过模型法对泄漏位置实时计算。结果表明：未泄漏稳态计算时,公式法和模型法的计算结果基本相同。管道泄漏后会产生负压波,导致全线压力降低,泄漏点上游流量增大,下游流量减小。压力波先后传播到管道首末端,在传播到管道首末端时会发生反射,随着压力波反射次数的增加,管内压力和流量会逐渐达到稳定状态。气体管道发生泄漏后,压力波向上下游传播,在各点产生的压力波幅呈指数规律衰减。利用管道泄漏后稳定状态时的起终点压力和流量结果计算得到的定位结果与真实值更接近。

Transient Simulation and Analysis of Gas Pipeline Leakage

Focusing on the possible leaking condition for the gas pipeline, based on the transient flow model of gas pipeline and the leakage boundary condition, the numerical simulation is used to simulate the change of pressure flow rate at any position of the pipeline after leaking. The leakage position is calculated in any time by the model method. The results show that the results of the formula method and the model method are basically the same. Pipeline leakage will bring negative pressure wave, leading to pressure drop across the line, the upstream flow flux of leakage point increases, and the downstream flow flux of leakage point decreases. The pressure wave spreads to the boundary of the pipeline successively, the reflection will occur in the transmission to the boundary of the pipeline, with the increase of pressure wave reflection frequency, the pressure and flow flux of the pipeline will gradually stabilize. After the gas pipeline leaking, the pressure wave propagates up and down, and the pressure amplitude at each point decays in exponential. Using the pressure and the flow flux in the steady state after the pipeline leakage, the location results will be closer to the real value.