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天然气在管网中不稳定流动问题可以采用各种数值解法并借助计算机来进行有效的分析，目前最广泛采用的数值法有特征线法、显示法和隐式有隐差分法等。与隐式法相比，特征线法和其它显示法的主要优点在于用它们能对各种边界条件进行显示处理，并只需较小的计算机存贮容量，但其时间步长和管段步长的比值要受到一定稳定条件的限制，这使得时间步长只能取得很小，如果分析过程较长时，就需消耗很长的计算时间。而隐式法的优点在于用它能采用较长的时间步长，并能保证计算结果的精度和稳定性，这就相应地减少了计算次数，但不足在于当分析的管网较大时，由于每一步要求解大型的非线性方程组，因此需要较多的计算机容量和花费较长的计算时间。为了克服这些方法的缺点，文章通过揉合特征线法和隐式法，提出了一种综合法，由此研制出的软件包克服了上述不足，并对四川几条管网系统进行了模拟，其计算结果与测量数据符合。
The instability flow problem of natural gas in the pipe network can be solved by various numerical methods and computerized analysis. The most widely used numerical methods are the characteristic line method, the display method, and the implicit implicit difference method. Compared with the implicit method, the main advantage of the feature line method and other display methods is that they can be used to display a variety of boundary conditions, and requires only a small computer storage capacity, but its time step and pipe step size The ratio is subject to certain stability conditions, which makes the time step can only be made very small, if the analysis process is longer, it takes a long time to calculate. Implicit method has the advantage of using it to take a longer time step, and to ensure the accuracy and stability of the calculation results, which reduces the number of calculations, but the downside is that when the analysis of the pipe network is large, Since each step requires solving a large set of nonlinear equations, it requires more computer capacity and takes longer computational time. In order to overcome the shortcomings of these methods, the article proposes a comprehensive method by combining the characteristic line method and the implicit method. The software package developed by the method overcomes the above shortcomings and simulates several pipe network systems in Sichuan. The calculated result is in accordance with the measured data.