设有复式空气阀的管道充、放水过程

Water filling and emptying process of pipeline with combined air valve

为了研究长距离有压管道充水和放水过程中管内气体压力的变化情况,并保证其运行中的安全,针对长距离有压管道的特点,对其充水和放水过程,采取了对整个管道进行分段处理、依次充水和放水的策略.对于分段后的每一段管道,建立了圆形管道内水体体积与水深关系的数学模型.按照小流量充水的原则,运用理想气体状态方程,结合复合式空气阀的进气和排气性质,在空气阀和泄水管布置情况已知的前提下,根据不同的充水流量和放水流量,计算各管段气体压力的变化情况.整个数值计算过程采用自编Fortran程序计算求解.计算结果表明:充水和放水的流量越大,对应管段的气体压力越大和越小,管道越危险;在不影响管道安全性的前提下,为了使管道尽快充满和放空,应采取较大的充水流量(16 m3/s)和放水流量(泄水阀全开).

In order to research the air pressure changes in water filling and emptying process of a long distance pressured-pipeline,sectional treatment and ordinal water filling and water emptying were adopted according to the characteristics of the pressured-pipeline.For each segment of the circular pipe,a mathematical model which involved the relationship between the water volume and water depth was established.On the basis of the definite positions of air valves and drain pipes as well as with the principle of small flow filling,the ideal equation concerning with the characteristics of air valve were calculated by Fortran programmed code for the various flow rates of both water filling and water emptying.The results show that the greater flow rate of the water filling and water emptying,the higher and lower the corresponding air pressure,and the higher risk of the pipe.The greater flow rate of water filling and water emptying should be accepted on the premise that the pipe is safe.The final filling flow rate is 16 m3/s,and the drain valves are full opening during water emptying process.