关键词: 水锤防护; 空气罐; 超压泄压阀; 高扬程超长距离; 供水工程;

Abstract: Based on the method of characteristic line, we established acalculation model containing control equation of air vessel node, boundary condition of overpressure relief valve, and then discussed the research and application of air vessel and overpressure relief valve in water supply project with high head and low flow.Firstly, we compared and analyzed the influence of the following two schemes on the water hammer during pump stopping period: no protective measures and combined protection of air vessel and overpressure relief valve.Then, for the control conditions, we compared and assessed three protection schemes, such as air vessel volume 60 m3 without pressure relief valve, air vessel volume 80 m3 without pressure relief valve, air vessel volume 60 m3 with pressure relief valve.The results showed that the combined protection of air vessel and pressure relief valve was beneficial to restrain the influence of positive and negative water hammer.Then, we optimized the shape parameters of air vessel and gaveaclosing law of the valve-behind pump that the valve could be closed in 10 seconds.Finally, according to the shape parameters of the optimized air vessel, we rechecked and calculated the pressure at characteristic points toverify effectiveness of combined protection.

Key words: water hammer protection; air vessel; overpressure relief valve; high-lift and long distance; water supply project;