输水管道系统气体特性与水流冲击截留气团研究

通过试验与理论相结合的方法,对输水管道系统气体特性与水流冲击截留气团进行了研究.研究表明,决定气团主要性质的气体多方指数n在输水管道系统发生水力过渡过程时存在较为显著的变化,并非单一常数,从而提出了相应的四过程:即压缩子过程1、膨胀子过程2、膨胀子过程3和压缩子过程4.在压缩子过程4与膨胀子过程2中,气体多方指数n取值为1.4~1.6;而在压缩子过程1与膨胀子过程3中,气体多方指数n取1.15.气体多方指数n的取值对压力水流冲击截留气团的结果有一定影响,n值越小,水流冲击截留气团的压力越大;反之越小.

Research on gas properties and current rush to interception air-mass in delivery pipeline system

According to the experimentation and the theory,research on gas properties and current rush to interception airmass in the delivery pipeline system are made.The studies indicated that the gas thermal insulation coefficient determining primary properties of the air-mass changes apparently instead of a single constant when hydraulic transition process happens So four appropriate processes are given,namely sub process 1 of compressing,sub-process 2 of inflating,sub-process 3 of inflating,and sub process 4 of compressing.In the sub-process 2 of inflating and sub process 4 of compressing,the gas thermal insulation coeff icient is 1.4~1.6,and is 1.15 in other two processes The value of gas thermal insulation coefficient has definitely influence on the result of the analytic root of current rush to interception air-mass in the delivery pipeline system The more small gas thermal insulation coefficient is,the more great the press of current rush to interception air mass is,and and vice versa.