燃气管网中大流量用户事故工况下动态模拟及分析

Dynamic Simulation and Analysis of Gas Network in Accident Condition of Large Low Gas User

摘要:

大型钢铁企业中高炉煤气透平因故突然停机时,超大的煤气流量突变将使管网压力急剧上升，可能会发生击穿排水密封罐而外泄煤气等安全事故.采用可压缩流体的高阶有限容积法(FVM)及其系列改进算法对此典型故障工况进行了动态分析.这对国内燃气管网动态分析中还在普遍应用的有限差分法和特征线法是更高层次的补充.利用FVM中稳定性较强的求解压力耦合方程半隐式方法(SIMPLE改进算法)，可以克服管网计算中各管段管径大小不同，在相连接处流量突变的困难.

Abstract:

When blast furnace gas turbine is suddenly stopped in large iron and steel enterprises due to the fault,gas pressure along the pipeline will steep rise for mutation of extra large gas flow,and this will lead to the security incident of gas leak as a result of water sealing breakdown.This paper presents a dynamic analysis of this typical malfunction condition by using compressible fluid high-order finite volume method(FVM) and its improved algorithm.The FVM method is a higher level supplement on characteristic method and finite difference method usually applied to the dynamic analysis of gas pipeline network.And the improved algorithm of semi-implicit method for pressure-linked equation(SIMPLE) which is more stable in FVM can overcome difficulties such as the great differences in the size of diameter and gas flow mutation at the joint of pipes.