【摘要】 天然气管道系统在运行过程中,由于供气量和用气量的变化、阀门的开关、压缩机的启停等,往往会 使管网系统处于不稳定的运行状态,加上目前管网运行中存在着区域供用气不平衡、管网服役时间长、运行环境恶 劣、管线破漏频繁、事故隐患严重等问题。因此对管道系统进行动态分析是很有必要的。文章通过建立管道数学 微分模型以及管网中非管元件数学微分模型,并用隐式差分法将偏微分模型转换为有限的差分方程,然后用牛顿 迭代法求解有限差分方程组,最后通过自制软件对某气田管网进行了仿真。仿真结果表明:各管道中的压力没有 超过管道允许压力,管网内压降较小。因此,可以适当增加输气量;而部分管段流量很小,利用率很低,则需要调整 输气方案。仿真结果与实际情况对比表明,该方法具有仿真精度高、求解速度快的优点。更多还原

【Abstract】 During operation process of a gas pipeline system, the pipeline system usually lies in unstable state because of the variation of gas supply and demand, the open and close of valves, the start and stop of compressors etc. In addition, there are many problems such as the imbalance of gas supply and demand between regions, the long service time, environment deterioration, frequent break and leakage and serious hidden accident risk etc. in the gas pipeline system. So, it is necessary to conduct the dynamic analysis of the gas pipeline system. With establishing mathematical differential models for the pipeline system and the non-piping units of the pipeline system, the hidden difference method is used to convert the partial differential models into the finite difference equations, and then the Newton iteration method is applied to solve the finite difference equations group. At last, with the software developed by us, the emulation is conducted for the pipeline system of some gas field. The emulation results show the pressure in the pipeline system doesn’t exceed the permitted pressure and the pressure drop is not big in the pipeline system. So, it is possible to increase the gas delivering volume properly. The flow rate is small in some sections of the pipeline with low using efficiency. Therefore, the gas transmission program should be adjusted. Comparing the emulation results with the real situation, it is proved the method has the characteristics of high emulation accuracy and fast solution velocity.更多还原