中文摘要：

天然气泄漏速率是模拟评价天然气管线泄漏事故过程中的重要因素之一,对其研究将有利于提高模拟评价结果的正确性。应用热力学和气体动力学理论,结合理想气体状态方程、绝热方程和能量守恒方程,研究分析了天然气管道的泄漏过程,分别给出了在临界泄漏阶段以及亚临界泄漏阶段的泄漏速率计算公式,为天然气管输安全工程的相关计算提供了可靠的理论依据。

英文摘要：

As the leakage rate is one of the important factors of natural gas pipeline operation that have not been well defined,it is necessary and important to give an analytical equation for the leakage flow rate of natural gas pipelines to improve the accuracy of simulation and estimation of leakage accidents.Based on the theories of thermodynamics and fluid mechanics,together with the use of ideal gas equation of state,adiabatic equation and energy conservation equation,the natural gas leakage process was studied and divided into two leakage phases,the critical phase and the sub-critical phase.Equations were obtained for calculating the leakage flow rate of the whole leakage process,and examples were given to analyze the influences of various parameters on leakage flow rate.