多股多层淹没射流消能水流流态及漩涡特性研究

Research on flow pattern and vortex characteristics of multi-strand and multi-layer submerged jets

利用多股多层淹没射流消能时消力池内流态非常复杂,有漩涡产生,可能威胁消力池安全进而危及枢纽工程。引入高速摄像系统,采用大比尺物理模型对消力池水流流态及漩涡特性进行了研究。结果表明:高低坎消力池底部产生较大尺度的回流旋滚,回流旋滚与消力池水体发生强剪切作用并在跌坎与池首的角隅处生成横轴漩涡和立轴漩涡,部分横轴漩涡横向发展会转变为近边墙立轴漩涡;水跃旋滚与消力池水体发生强剪切作用在跌坎与池首的角隅处生成立轴漩涡和纵轴漩涡;横轴漩涡、立轴漩涡和纵轴漩涡是间歇性、随机和游移的。

In energy disspation with muhi - strand and muhi - layer submerged jets, the flow state in energy dissipation pool is very eomplieated, produeing swirls and threatening the safety of the energy pool and projeet. In this paper, the flow pattern and eddy eharaeteristies are researehed with the large sealed physieal model and high speed video system. The observed images show that large swirl produeed near the bottom of the energy dissipation pool; strong shearing aetion between the swirl and the water body eauses horizontal vortex and vertieal vortex in the eorners of the drop sill and pool head, and some axial vortex develop later- ally and transform into vertieal vortex near the side wall; strong shear aetion between jump eddy and water body in stilling pool eauses vertieal vortex and longitudinal vortex in the eorner of the drop sill and pool head. Horizontal, vertieal and longitudinal vortexes are intermittent, random, and drifted.