基于特征线法的天然气管道放空时间的计算

Characteristic method based calculation of venting time for natural gas pipeline

天然气管道放空是压力、温度、气体流速都随时间变化的复杂过程,为准确计算长输管道天然气的放空时间,以放空管路为研究对象,建立非稳态的偏微分方程组,利用特征线方程将偏微分方程组转化为全微分方程组,并进行数值求解,计算出天然气管道放空所需时间。该方法的计算结果与工程实际中的管道放空数据吻合良好,可以较准确地计算长输天然气管道放空所需时间。

Venting of natural gas pipeline is a complex process with pressure, temperature and gas velocity varying with time. To correctly calculate the venting time of long-distance natural gas pipeline, the unsteady partial differential equations are established for venting lines. Then, these partial differential equations are transferred to total differential equations by characteristic line equation and solved to get the venting time of the natural gas pipeline. The calculation results of this method agree well with the venting line data in engineering practice, which indicates that this method can correctly calculate the venting time of natural gas pipeline.