关键词:

混合格式, 双曲守恒律, 天然气管线, 瞬变流动, TVD格式, 波动

Abstract:

The mathematical model describing transients in natural gas pipelines constitutes a non-homogeneous system of non-linear hyperbolic conservation.The time splitting approach was adopted to solve this non-homogeneous hyperbolic model.At each time step，the non-homogeneous hyperbolic model was split into a homogeneous hyperbolic model and an ordinary differential equation operator.An explicit 5-point，second-order-accurate total variation diminishing（TVD）scheme together with the Lax-Wendroff scheme to treat the neighborhood nodes of boundary,was formulated to solve the homogeneous system of non-linear hyperbolic conservation.The method of characteristics（MOC）was used to treat the boundary conditions at the inlet and outlet of the pipeline.An extreme condition involving instantaneous closure of a downstream valve and a real long pipeline’s transients were used to test the effectiveness of the hybrid schemes.The simulation results showed that the hybrid TVD/LW schemes could simulate real situation of the physical variables in a transient process successfully.

Key words:

混合格式, 双曲守恒律, 天然气管线, 瞬变流动, TVD格式, 波动