| 摘要: |
| 【目的】分析泵输水系统因事故停泵引起的水锤问题，为泵站管线的安全运行提供参考。【方法】根据流体力学原理，建立有压管道非恒定流动的水锤数学模型，利用特征线法进行数值模拟计算；结合山西省庄头支线泵站的特点，在泵出口安装两阶段关闭蝶阀和沿管线布设空气阀的联合防护措施下，分析了其水力过渡过程。【结果】泵出口两阶段关闭蝶阀在快关 9 s/70°和慢关 63 s/20°时，水泵机组倒转转速由额定转速的1.41倍降低为无阀防护时的0.94倍，最大倒泄水量由93.47 m3降低到12.3 m3；在液控蝶阀和空气阀联合防护下，管线负压由－6.9 m降低为－2.0 m。【结论】通过合理控制蝶阀快慢关闭时间及角度，能显著降低水泵机组倒转和倒泄流量；调整空气阀布设位置、口径及进出口流量系数，可使沿线负压降低到管道承受范围之内，从而保证供水工程的安全稳定运行。 |
| 关键词: 泵输水系统 停泵水锤 数值模拟 空气阀 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目（91230111，11361002）；北方民族大学科学研究项目（2014XBZ16）；宁夏水利厅水资源项目（宁水资发［2013］13-20） |
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| Numerical simulation and protection of water hammer in pumping water supply system |
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LÜ Sui-ju,FENG Min-quan,LI Chun-guang
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| Abstract: |
| 【Objective】 This study investigated water hammer problem caused by accidental pump stop in pumping water supply system to provide reference for safe operation of pumping station.【Method】Water hammer mathematical models of unsteady flow in pressure pipeline were established based on principles of fluid mechanics,and characteristic method was used in simulation of the flow movement equations.Combined with the characteristics of Zhuangtou pump station in Shanxi province,hydraulic transient process under the combined protective measures of two stage closed valve and air valve was analyzed.【Result】Reverse speed of pumping units under the fast closing 9 s/70° and slow closing 63 s/20° of butterfly valve in pump outlet decreased from 1.41 times of the rated speed to 0.94 times of the rated speed and the maximum pour water discharge reduced from 93.47 m3 to 12.3 m3.With the joint protection of hydraulic control butterfly valve and air valve,negative pressure in pipeline reduced from －6.9 m to －2.0 m.【Conclusion】The pumping units reverse speed and the maximum pour water discharge could be effectively reduced by the reasonable control of butterfly valve closing time and angle.The pipe negative pressure could be effectively reduced by adjusting the position of the air valve,the caliber of the valve and flow coefficient. |
| Key words: pressure water supply system pump-stop water hammer numerical simulation air valve |
