Simulation Of Natural Gas Pipeline Network Under Unbalanced Inlet And Outlet Flow

The natural gas energy industry has developed rapidly in recent years.The proportion of natural gas consumption in fossil energy has been increasing.The construction of natural gas pipelines has also developed rapidly.The scale of the national natural gas pipeline network is becoming more and more perfect.At the same time,the rise of hydrogen energy and natural gas mixed with hydrogen transmission has also brought new challenges and opportunities to China’s natural gas pipeline network supporting technology.The simulation technology of natural gas pipeline network is one of the core technologies of natural gas pipeline network,but the simulation technology in China still mainly depends on foreign simulation software.This paper describes and analyzes the basic model and relevant solution methods of natural gas pipeline network simulation,adopts the fast simulation solution algorithm based on linearization,simulates the transient process state of natural gas pipeline network,carries out the transient operation analysis of the influence of natural gas components,and carries out the relevant calculation and analysis of natural gas component tracking.Under the condition that the simulation accuracy is not affected,the Taylor linearization expansion method is used to linearize the transient model of natural gas pipeline network.The linearized discrete equations are obtained by implicit difference discretization.The linearized fast solution method is applied to the transient simulation of single pipeline and trunk pipeline network.The calculation results of off load pipe network of long-distance natural gas trunk line show that the energy head characteristic curve of the compressor will move down after natural gas is mixed with hydrogen.The compressor will need a higher speed when transporting hydrogen mixed natural gas at the same capacity.With the increase of hydrogen mixing ratio,the pressure drop along the pipeline will decrease and the end pressure will increase.Based on the fast linearization simulation algorithm of natural gas pipeline network,the component tracking research of natural gas trunk pipeline network is carried out by coupling gas component convection equation and gas physical property state equation.Combined with the calculation results of the component tracking example,the effectiveness of the natural gas component tracking convection equation is verified,which can better describe the migration of natural gas components under the condition of hydrogen doping,in order to provide a basis for the operation of the pipeline of the hydrogen doped natural gas pipeline network.