跌流竖井入流水舌处内嵌圆弧板的结构优化数值研究  

Numerical Study on Structural Optimization of Setting an Embedded Curved Plate at Inlet Tongue of Plunging-type Dropshaft

作　　者：魏佳芳 张源 芦三强 黄盈盈 南军虎[1] WEI Jia-fang;ZHANG Yuan;LU San-qiang;HUANG Ying-ying;NAN Jun-hu(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050

出　　处：《水电能源科学》2024年第4期80-84,共5页Water Resources and Power

基　　金：国家自然科学基金项目(51509123);甘肃省青年科技基金计划项目(22JR5RA287);兰州理工大学红柳优青人才计划(062004);兰州理工大学博士科研启动项目(061908)。

摘　　要：跌流竖井是排水系统中结构简单且应用广泛的排水基础设施之一,但该结构入流水舌处的水气两相作用剧烈、流态复杂,且在该处常常出现竖井内的最大负压,也就容易从外界大量吸气造成下游管道臭气逸散、井喷或爆管等问题。为此,提出在竖井水舌处设置内嵌圆弧板的结构优化方法,从而有效改善入流水舌流态,降低竖井内气压值和梯度变化,并减缓竖井从外界的吸气程度。在此基础上,采用Fluent三维数值模拟手段,对比分析了结构优化前后的流态、气压梯度、流速及水气分布等特性。结果表明,经过优化后的竖井模型改变了入流水舌处的液体流态,水流入射角度减小,水流撞击点的位置降低,竖井水舌处的负压值明显降低,垂直管内的整体压力梯度变化幅值减弱,从外界卷吸的气量也大幅度减小。可见所设计的新型竖井结构优化方法对跌流竖井入流水舌问题有较好的改善作用,同时也为排污管道竖井设计及优化提供一定的参考。The plunging-type dropshaft is one of the drainage infrastructure with simple structure and wide application in the drainage system.However,the water-gas two-phase action at the water tongue of the structure is intense and the flow pattern is complex,and there is often the maximum negative pressure in the dropshaft,which is easy to cause a large number of inspirations from the outside to the downstream pipe odor escape,blowout or pipe explosion and other problems.Therefore,this paper proposes a structural optimization method of setting an embedded circular arc plate at the water tongue of the dropshaft,which can effectively improve the flow pattern of the flowing water tongue into the dropshaft,reduce the pressure value and gradient change in the dropshaft,and slow down the suction degree of the dropshaft from the outside.The 3D numerical simulation method of Fluent is used to compare and analyze the characteristics of flow pattern,pressure gradient,velocity and water and air distribution before and after structure optimization.The results show that the optimized dropshaft model changes the liquid flow pattern at the inlet of the water tongue.Meanwhile,the water incident angle,the water impact point and the negative pressure value at the water tongue decrease obviously.The overall pressure of gradient variation amplitude in the vertical pipe of the dropshaft weakens,and the gas volume which sucks from the outside of the dropshaft also reduces greatly.The new optimization method of shaft structure designed in this paper has a better effect on the problem of falling shaft into the flow tongue,and also provides a certain reference for the design and optimization of dropshaft.

关 键 词：跌流竖井 入流水舌 内嵌圆弧板 流态改善 数值模拟 

分 类 号：TV134[水利工程—水力学及河流动力学] TU992[建筑科学—市政工程]