NUMERICAL AND ANALYTICAL STUDY ON FLOW CHARACTERISTICS AND FUNDAMENTAL MECHANISM IN HIGH-PRESSURE GAS PIPELINE LEAKAGE

Abstract

High-pressure gas pipeline leakage is one of the major concerns in the field of pipeline security. To build up a smart monitoring system integrating the merits of various leakage detection methods, a better understanding of aerodynamic and thermodynamic characteristics at the onset of high-pressure pipeline leakage is necessary. Computational fluid dynamics (CFD) was employed in the thesis to explore the flow behaviours under different scenarios of gas pipe leakage and elucidate the fundamental fluid physics of leakage phenomena. The transient numerical analysis using large eddy simulation (LES) approach was carried out in two aspects to disclose the features of internal pipe flow during above-ground leakage and external dispersion flow during underground pipeline leakage. In addition to the numerical analysis, a new real-gas analytical model was proposed to overcome the drawbacks of traditional ideal-gas models, providing an effective tool in the responsive solution of high-pressure gas pipe leakage.