喷嘴间距对双股平面射流冲刷的影响  

Influence of nozzle distance on scour by two plane water jets

作　　者：顾磊[1] 倪福生[1] 李雯[1] 徐立群[1] 

机构地区：[1]河海大学疏浚技术教育部工程研究中心,江苏常州213022

出　　处：《泥沙研究》2016年第6期32-37,共6页Journal of Sediment Research

基　　金：中央高校基本科研业务经费项目(26120132013B10314)

摘　　要：喷嘴间距是影响射流冲刷效果的关键参数。利用FLOW-3D软件对双股平面射流的沙床冲刷进行了数值模拟。固定沙床粒径和冲刷靶距,比较了不同喷嘴间距下冲刷沙坑的形状、深度和面积,分析了冲刷形成的流场和浓度分布。研究发现,两股射流之间会形成漩涡,这种漩涡会消耗射流的能量,但同时又促使中间区域沙床的泥沙残留减小。在某一喷嘴间距下冲坑的深度会出现极小值,设计喷射机具时应避免此种布置。同时存在最佳喷嘴间距,可确保冲刷区域无残留浅点条件下冲坑深度和面积达到最大,获得较佳的冲刷效果。Nozzle distance is a key parameter to influence the scouring of sediment by water jets. This paper the scouring of sand beds by two plane water jets is simulated by FLOW - 3D numerical model. Scouring effects at different nozzle distances are compared, such as scour profile, scour depth and scour area. The flow field and the concentration distribution are analyzed. This study reveals that a vortex is generated in the area between two water jets. The vortex wastes the energy of water jets but decreases the remains on the sand bed between two nozzles. A minimal scour depth occurs at a certain nozzle distance,which must be avoided in the jet equipment design. In addition, there is an optimal nozzle distance, at which no remained ridge appears and the scour depth and the scour area reach maximum values. Consequently,a preferred scouring effect can be ob- tained at this condition.

关 键 词：双股平面射流 喷嘴间距 冲刷效果 FLOW-3D 

分 类 号：TV851[水利工程—水利水电工程]