驼峰式长距离输水管线单向调压塔水锤防护研究

Research on Water Hammer Protection of One-way Surge Tank in Hump Type Long Distance Water Transmission Pipeline

驼峰式管线作为长输水系统的典型布置方式,中间凸起管段的局部水锤特性及其水锤防护问题复杂。通过驼峰式管线高点下游侧管线坡度与水力坡度的比较分析,阐明了单向调压塔对驼峰式长距离输水管线的防护机理,并推导了单向调压塔设置高度的近似解析公式。进一步基于有压输水管道特征线法,融合单向调压塔和调流阀等水力边界,建立了相应的输水系统水锤分析模型,开展了系统的水锤防护及其优化研究。分析表明,基于建立的单向调压塔设置分析方法,在驼峰式管线合理设置单向调压塔,能够有效实现系统的水锤防护,并可考虑管线布置特性进一步优化,数值计算和理论分析一致;单向调压塔直径和阻抗孔直径是评估单向调压塔水锤防护效果的重要参数,均存在一最优数值解,继续增大单向调压塔直径或阻抗孔直径对改善水锤防护效果作用很小。

As a typical arrangement of long water conveyance system,the local water hammer characteristics and water hammer protection of hump pipeline in the middle convex section are complex.Through the comparative analysis of hydraulic slope and the slope at the downstream side of the high point of the hump type pipeline,the protection mechanism of the one-way surge tank for the hump type long-distance water transmission pipeline was clarified,and the approximate analytical formula for the setting height of the one-way surge tank was derived.Based on the characteristic line method of pressurized water transmission pipeline,the corresponding water hammer analysis model of water transmission system was established by integrating the hydraulic boundary of one-way surge tank and flow regulating valve,and the systematic study on water hammer protection and its optimization were carried out.The analysis shows that based on the established analysis method for the setting of one-way surge tank,the reasonable setting of one-way surge tank in the hump type pipeline can effectively realize the water hammer protection of the system,and can be further optimized by considering the pipeline layout characteristics,the numerical calculation is consistent with the theoretical analysis.The diameter of the impedance hole and the diameter of the one-way surge tank are important parameters to evaluate the water hammer protection effect of the one-way surge tank.There is an optimal numerical solution for both of them,and the continuous increase of the diameter of the impedance hole or the diameter of the one-way surge tank has little effect on improving the water hammer protection effect.