Efficient and physically consistent transient modeling of gas flows in pipelines

Transient simulation of compressible gas flows (e.g., CO2, H2, and CH4) in pipelines plays a critical role in system monitoring and operational decision-making in industrial applications, yet large-scale and real-time applications require modeling frameworks that are both efficient and physically reliable. Distributed-parameter models provide high physical fidelity, but their computational cost limits their applicability in such scenarios. In contrast, lumped-parameter models (LPMs) offer high computational efficiency, yet they may exhibit spurious transient modes, manifested as observable nonphysical oscillations, particularly in long-distance pipeline simulations. In this study, a physically consistent transient simulation framework is developed to investigate and suppress such behaviors. These spurious modes are shown to be closely associated with a mismatch between the finite disturbance time and its lumped numerical representation. The proposed framework combines a refined spatial integration scheme based on the Euler–Maclaurin expansion, an adaptive time-delay correction to account for finite disturbance propagation, and an equivalent inertia factor treatment to mitigate phase-leading phenomena associated with inertia bias. The proposed framework is evaluated through a series of numerical experiments, including comparisons with finite-difference method under different operating pressures, gas compositions, and transient boundary profiles. Within the tested cases, the proposed framework improves simulation accuracy and reduces the computational cost relative to the finite-difference benchmark while retaining a low-dimensional formulation. These findings provide practical guidance for improving the representation of finite disturbance propagation and inertia-related effects in LPM of compressible gas flows.