泵站有压输水系统启动过程中蝶阀非定常流场研究  

Study on unsteady flow field of butterfly valve in startup process of pressure-driven water diversion system in pumping station

作　　者：邹志超[1] 王福军[1,2] 王玲 ZOU Zhichao;WANG Fujun;WANG Ling(College of Water Resources ＆ Civil Engineering,China Agricultural University,Beijing 100083,China;Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System,Beijing 100083,China)

机构地区：[1]中国农业大学水利与土木工程学院,北京100083 [2]北京市供水管网系统安全与节能工程技术研究中心,北京100083

出　　处：《水利学报》2018年第6期678-686,共9页Journal of Hydraulic Engineering

基　　金：国家自然科学基金项目(51779258;51621061)

摘　　要：蝶阀广泛应用于有压输水系统,其开启过程是输水系统启动运行的必经阶段。在开启过程中,阀板需按预定的规律在流场中做旋转运动,具有变压差变截面的特点。本文针对泵站加压输水系统,采用一维/三维耦合计算思路,对蝶阀上下游的管路段按准恒定假设基于伯努利方程、对蝶阀所在的三维流体域基于动网格策略,构建了蝶阀开启过程数值分析方法,提出了模拟计算的动态边界条件及数据更新方式,对蝶阀开启过程非定常特性进行了三维数值模拟。研究结果表明,当阀板转角由0°匀速增大至90°,管道流量在阀板转角0~45°范围内快速增长,在45°时达到额定流量的90%,之后流量增长速度变缓。阀板水力转矩呈先快增后慢减的变化趋势,最大水力转矩出现在阀板转角20°时。从蝶阀前后流场可以看出,在阀板下游具有从两个主涡到流线平顺的演化特征。该研究揭示了蝶阀开启过程中水力瞬变演化机理,为优化蝶阀设计和输水系统稳定运行提供了参考。Butterfly valves are widely used in pressure-driven water diversion systems. The opening processof the valve is a necessary stage for the system operation. In this process, the valve disc rotates in theflow field according to prescribed law, which will induce the variable-pressure and variable-section tran-sient flow. In this study,based on the quasi-constant assumptions and Bernoulli equation for the pipe sec-tions upstream and downstream of the butterfly valve, and the dynamic grid strategy for the 3 D fluid do-main,a numerical method for simulating the butterfly valve opening process is presented. This method com-bines the one dimensional and three dimensional calculations. The dynamic boundary conditions and data up-dating scheme used for simulation are proposed. The three dimensional numerical simulations of unsteadycharacteristics of butterfly valve opening process are carried out. The results show that the flow rate increas-es rapidly and runs up to 90 % of the rated flow with the valve disc angle varying from 0° to 45°, andthen increases slowly with the disc angle increasing from 45° to 90°. The hydraulic torque of the valvedisc increases rapidly and then decreases slowly,and the maximum value of hydraulic torque appears whenthe disc angle is 20°. It can be found that the downstream flow field of the valve disc has specific evolu-tion characteristics, which show the transformation from two main vortices to smooth streamline. This studyreveals the mechanism of hydraulic transient change during the opening of butterfly valve. The results couldbe used to direct optimization design of butterfly valve and stable operation of water supply system.

关 键 词：泵站 有压输水 蝶阀开启过程 流场演变 

分 类 号：TV732.7[水利工程—水利水电工程] TV134.1