gas pipeline, leakage model, leakage rate, joule-thomson effect, research progress, Oils, fats, and waxes, TP670-699, Gas industry, TP751-762

Leakage amount is an important basis for consequence assessment of gas pipeline leakage accident.Once the pipeline leakage accident occurs, the negative pressure wave will be transmitted from the leakage place to the upstream and downstream of the pipeline.The huge pressure difference inside and outside the pipeline will induce the JouleThomson effect, which may lower the temperature of the gas, condense and separate out the heavy components in the gas.However, the dynamic flow cofficient makes it even harder to calculate the flow field inside the pipeline.By investigating the existing leakage rate models of gas pipelines, the research progress of current leakage rate models was summarized and the limitations of each model were analyzed.Most of the pipeline leakage rate models are based on computational fluid dynamics with better computational accuracy than traditional models.However, the leakage rate in real time cannot be calculated by coupling the changes of hydro-thermal parameters across the pipeline.Therefore, the development of algorithms used to solve the leakage model of long-distance gas pipelines will be an important research direction in the future.