摘要
运用计算流体动力学(computational fluid dynamics,CFD)方法,基于不可压缩的Navier-Stokes方程,对真实尺度下的高雷诺数圆管湍流潜射流与自由表面的相互作用进行了数值研究.在圆管湍流射流过程中运用Realizable k-ε的雷诺时均(Reynolds average navier-stokes,RANS)模型,射流停止后,采用大涡模拟(large eddy simulation,LES)方法模拟大尺度涡在背景流体中的演化.研究表明:随着时间的推移,湍射流涡结构从球形冠状结构向具有准二维的流动特征转变,涡的前端出现明显的塌陷现象,并逐渐达到某种相对稳定的状态;从流场中纵剖面上来看,射流流体逐渐上升并向自由表面聚集,并有流体在自由表面处反射,形成斜向下的流动,同时中纵剖面上形成许多局部微小的涡结构;从自由表面上来看,流场从初始的具有速度辐射与速度汇聚中心而不形成涡的阶段向表面流体主要向前流动并出现涡演化的阶段转变.
Based on the incompressible Navier-Stokes equation,the computational fluid dynamics(CFD)method is adopted to numerically investigate the interaction between the free surface and the submerged turbulent round jet with high Reynolds number in the real condition.The Reynolds Average Navier-Stokes(RANS)based on the Realizable k-εmethod is adopted for the turbulent jet flow in a circular tube.After the jet flow stops,the large eddy simulation(LES)method is used to investigate the evolution of large-scale eddy in the background fluid.The results show that,as time goes on,the turbulent vortex structure changes from a spherical canopy structure to a quasi-two-dimensional flow characteristic,the front end of the vortex exhibits obvious collapse phenomenon and gradually reaches a relatively stable state;In the middle longitudinal section of the flow field,the jet fluid gradually rises and accumulates towards the free surface,and some fluids reflect at the free surface,forming oblique downward flows and many small vortex structures are formed;On the free surface,the flow field changes from the initial stage where there appears a velocity radiation center and a velocity convergence center but without the vortex formation to the stage where the surface fluid flows mainly forward and vortex evolution occurs.
作者
古磊
陈科
盛立
尤云祥
GU Lei;CHEN Ke;SHENG Li;YOU Yunxiang(State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration,Shanghai 200240,China;No.92578 Unit of PLA,Beijing 100161,China)
出处
《江苏科技大学学报（自然科学版）》
CAS
北大核心
2021年第4期1-8,共8页
Journal of Jiangsu University of Science and Technology:Natural Science Edition
基金
国家自然科学基金资助项目(11802176,51979279)。
关键词
圆湍潜射流
高雷诺数
自由表面
浅水
submerged turbulent round jet
high Reynolds number
free surface
shallow water
