中文摘要：

为进行燃气管网系统优化和提高管网输运系统的安全性，以三大守恒方程为基础，建立了等温和非等温条件下的燃气管网稳动态仿真理论模型．以有限差分法为基础，得到了上述模型的求解方法，并加入了耗散项，改进了求解方法的稳定性．通过增加初始点和延长出口点的方法，简化了模型的求解．北京六环天然气管网动态仿真结果表明，与实际压力和流量值综合相对误差分别为1．21％和2．62％，验证了模型及求解青津湘可靠一阵．

英文摘要：

In order to optimize the gas pipeline network and improve the security performance of gas transmission system, the isothermal and non-isothermal simulation models of gas network are set up based on three conservation equations. The solving method of this model is achieved on the basis of finite difference method, and stability of the solving method is improved by adding dissipation terms. The solving process of this model has been simplified by adding original point and prolonging exit point. Taking a gas pipeline network in Beijing city as an example, the relative errors between pressure and flux obtained by this model and those obtained practically are 1.21% and 2.62% , respectively, which validates the reliability of the model.