| 引用本文: | 刘 灿,王永宁,范 征,等.轴流式止回阀与水击泄放阀组合的水锤防护系统研究[J].灌溉排水学报,2024,43(S1):9-14. |
| LIU Can,WANG Yongning,FAN Zheng,et al.轴流式止回阀与水击泄放阀组合的水锤防护系统研究[J].灌溉排水学报,2024,43(S1):9-14. |
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| 摘要: |
| 【目的】研究减小长距离高扬程输水工程中水锤作用对建筑物安全运行的不利影响，保障管道等建筑物安全。【方法】基于瞬变流理论及特征线法结合水柱分离数学模型的方法，并考虑水锤防护设备的边界条件，运用水锤仿真计算软件对系统停泵水锤进行数值计算。对传统的“单向调压塔+空气阀”和“水击泄放阀+轴流止回阀+空气阀”2种水锤防护措施进行比较，验证轴流止回阀与水击泄放阀组合的水锤防护系统防护效果。【结果】经过计算及后期实际工程多年运行验证后表明在长距离高扬程输水工程中：2种水锤防护方案对事故停泵下管线高压及负压水锤均有一定的防护效果。“单向调压塔+空气阀”的防护措施能使管道内负压由汽化负压-8.4 m降到了-6.9 m水头压力，管道正压最大值由3.04 Mpa降低至2.98 Mpa，但若要继续降低管线负压则需再增加调压塔数量，增加工程投资，经济性上并无优势；“水击泄放阀+轴流止回阀+空气阀”的水锤防护措施，能够有效防护因停泵引起的高低压水锤及水泵倒流倒转等问题，管道内负压由已汽化负压降到了-5 m水头压力，使其系统内最高压力由3.04 Mpa降低至3.0 Mpa，管道最大压力控制在稳态压力的1.2倍之内。【结论】工程竣工多年运行验证，此水锤防护系统只需在输水系统中设1处水击泄放阀和轴流止回阀即可实现有效的防护因停泵引起的高低压水锤及水泵倒流倒转等问题，具有相同的可靠性和更高的经济性，可为类似工程防水锤设计提供依据。 |
| 关键词: 长距离高扬程输水工程；水锤水力仿真计算；轴流式止回阀 |
| DOI：10.13522/j.cnki.ggps.2023582 |
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| Research on the water hammer protection system of the combination of axial flow check valve and water hammer relief valve |
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LIU Can, WANG Yongning, FAN Zheng, LIU Wei
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1. Gansu Water Resources and Hydropower Survey and Design Research Institute Co., Ltd, Lanzhou 730000, China;
2. Qingyang Yanhuanding Yanghuang Continuation Project Construction Management Bureau, Qingyang 745000, China
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| Abstract: |
| 【Objective】 To reduce the adverse effects of water hammer on the buildings in long-distance high-lift water conveyance projects, and to ensure the safety of pipelines buildings. 【Method】 Based on the transient flow theory and the characteristic line method combined with the mathematical model of water column separation, and considering the boundary conditions of water hammer protection equipment, the hydraulic simulation software was used to calculate the water hammer hydraulic. The traditional “one-way surge tank + air valve” and “water hammer relief valve + axial flow check valve + air valve” two water hammer protection measures were numerically calculated and compared to verify the protection effect of the water hammer protection system combined with the axial flow check valve and the water hammer relief valve. 【Result】 After calculation and verification of many years of operation in the later actual project, it was shown that in the long-distance high-lift water conveyance project, the two water hammer protection schemes have certain protective effects on the high-pressure and negative-pressure water hammer of the pipeline under the accident pump shutdown. The protective measures of “one-way surge tank + air valve” can reduce the negative pressure in the pipeline from the vaporized negative pressure -8.4 m to the head pressure of -6.9 m, and the maximum positive pressure of the pipeline is reduced from 4.25 Mpa to 2.98 Mpa. However, if we want to continue to reduce the negative pressure of the pipeline, we need to increase the number of surge tanks and increase the project investment, and there is no economic advantage. The water hammer protection measures of “water hammer relief valve + axial flow check valve + air valve” can effectively protect the high and low pressure water hammer and pump backflow caused by pump stoppage. The negative pressure in the pipeline is reduced from the vaporized negative pressure to the -5 m head pressure, so that the maximum pressure in the system is reduced from 4.25 Mpa to 3.0 Mpa, and the maximum pressure in the pipeline is controlled within 1.2 times of the steady-state pressure. 【Conclusion】 Years of operation after the completion of the project has verified that the water hammer protection system only needs to set up a water hammer relief valve and an axial flow check valve in the water conveyance system to achieve effective protection against high and low pressure water hammer caused by pump shutdown and pump backflow and other issues. It has the same reliability and higher economy, and can provide a basis for the design of water hammer in similar projects. |
| Key words: long-distance high-lift water conveyance project; water hammer hydraulic simulation calculation; axial flow check valve |
