Unified Fault Modeling for Non-Isothermal Gas Pipeline Based on Linear Graph Method in Industrial Parks

Pipeline fault diagnosis techniques is of great significance to improve the efficiency of pipeline transportation. The mechanism model, an important component of the hybrid mechanism-data-driven method, effectively describes the physical process of faults with high interpretability. However, the existing fault models have been studied for the isothermal gas pipeline. Therefore, there is an urgent need for a unified framework to realize fault modeling of the hydraulic and thermal models in non-isothermal gas pipeline. To address this problem, this paper establishes a fault model based on linear graph method for the industrial gas pipeline, which can not only monitor the transient characteristic of the gas temperature during the leakage process, but also provide a mechanism model support for pipeline fault diagnosis technology based on the hybrid mechanism-data-driven method. The fault model of non-isothermal gas pipeline is established based on the fundamental equation of one-dimensional gas flow. Linear graph model of non-isothermal gas pipeline with the leakage fault is descripted by generalized system elements of linear graph theory. The experimental analysis is carried out employing the real user data from an industrial park. The effectiveness of the proposed fault model is verified by comparison with the APROS<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TM</sup> simulation model.