泵后管线先降后升的长距离输水系统水锤防护

针对泵后管线先降后升的长距离大流量输水系统,当水泵发生抽水断电时泵后管线高点处易出现负压的特点,提出了一种调压塔联合末端调流阀的停泵水锤防护方案,并基于瞬变流计算的特征线法建立了全系统水力过渡过程的数学模型,模拟了系统停泵水锤全过程.结合某实际输水工程,探究常规调压塔防护方案的调压塔最小面积,给出泵后设调压塔结合末端调流阀联动关闭的水锤防护方案的参数选取原则,对比常规调压塔防护方案与泵后设调压塔结合末端调流阀联动关闭的水锤防护方案对停泵水锤的影响.计算结果表明,常规调压塔防护方案调压塔面积达到1 100 m²,投资成本巨大;调压塔结合末端调流阀联动关闭的防护方案末端调流阀关闭过快会引起管道正压过大,关闭过慢会导致管道水流回流能力不足,选取合适的末端调流阀关闭时间,在满足系统水锤防护标准的前提下,可以有效地减小调压塔面积.

Long-distance water hammer protection of pipeline after pump being first lowered and then raised

The long-distance water transmission system of the long-distance water transmission system after the pump is prone to negative pressure when the pump is de-energized. a pump-stop water hammer protection scheme of pressure regulating tower combined with end regulator valve was proposed, and a mathematical model of the hydraulic transition process was established based on the characteristic line method of transient flow calculation to simulate the whole process of pump-stopping water hammer. Combined with the actual project, the minimum area of the pressure regulating tower of the conventional pressure regulating tower protection scheme was explored, and the parameter selection principle of the water hammer protection scheme of the pressure regulating tower set after the pump combined with the end regulator valve linkage was given, and the influence of the water hammer protection scheme of the conventional scheme and the water hammer protection scheme of the pressure regulating tower set behind the pump combined with the end regulator valve linkage closure on the water hammer of the pump was stopped. The results show that the area of the conventional scheme voltage regulating tower is 1 100 m². The protection scheme of the pressure regulating tower combined with the lin-kage closing of the end regulator valve will cause the pipeline positive pressure to be too large, while it closes so slow as to lead to insufficient water flow return capacity of the pipeline, select the appropriate end regulator closing time, under the premise of meeting the system water hammer protection standards, the area of the pressure regulating tower can be effectively reduced.