长距离树状重力流系统水锤防护研究

Study on water hammer protection of long distance treelike gravity flow system

为研究不同工况下长距离树状重力流系统水锤特性,应用水锤基本理论和特征线法,结合某实际工程,对长距离树状重力流系统在稳态、末端阀门同时及分别关闭和开启等不同工况下的水力过渡过程进行分析计算。结果表明:随着关阀时间的延长,管道中的最大压力逐渐减小,最小压力逐渐增大,当关阀时间达到一定长度时,管道中最大、最小压力基本保持不变;管道末端阀门同时关闭时,管道中的最大压力明显大于管道末端阀门分别关闭时的压力;管道末端阀门的开启时间的变化对管道中正压和负压的影响不大;管道末端阀门同时及分别开启时管道中的正压相差不大;管道末端阀门分别开启时管道中的负压比阀门同时开启时的负压小。

In order to study the water hammer characteristics of long distance treelike gravity flow system in different working conditions,the basic theory for water hammer and characteristic line method are applied.Combined with a practical project,the hydraulic transition process of long distance treelike gravity flow system is analyzed and calculated under different conditions such as steady state,simultaneous and separate closing and opening of terminal valves.The results show that with the extension of valve closing time,the maximum pressure in the pipeline decreases gradually and the minimum pressure increases gradually.When the valve closing time reaches a certain length,the maximum and minimum pressure in the pipeline remain basically unchanged.When the valves at the end of the pipeline are closed at the same time,the maximum pressure in the pipeline is obviously greater than the pressure when the valves at the end of the pipeline are closed separately.The change of the opening time of the valve at the end of the pipeline has little effect on the positive pressure and negative pressure in the pipeline.There is little difference in the positive pressure in the pipeline when the valve at the end of the pipeline is opened at the same time and separately.When the valves at the end of the pipeline are opened separately,the negative pressure in the pipeline is smaller than that when the valves are opened simultaneously.