半球阵列式涡流发生器湍流尾迹流动特性研究

Study on Flow Characteristics of Turbulent Wakes in Hemispheric Array Eddy Current Generator

利用DDES延迟分离涡模拟研究了半球状的涡流发生器尾迹区域的流动特性,包括了速度场以及涡量场,研究发现尾迹区域的速度场,涡量场呈现出不同的发展趋势,速度场在初始角度尾流开始分离,随着角度的增加,由流动分离再趋向于整体,尾迹区域的宽度与长度的变化经历了加速下降区,相对缓慢加速区,以及平缓过渡区三区域,涡量场整体趋向于分离状态,随着角度增加脱落的漩涡越来越大,涡量保持区的长度变长。涡量场与速度场在总体上呈现出不同的流体动力特征。

The flow characteristics of the hemispherical vortex generator wake region are studied byDDES delayed separation eddy simulation. The velocity field and the vorticity field are studied. The velocity field of the wake region is found. The vorticity field shows different development trends. The velocity field at initial angle wake begins to separate,the flow separation then tends to the whole. The width and length of the wake region change through the accelerated descent zone,the relatively slow acceleration zone,and the smooth transition zone,the vorticity field. he vortex shedding becomes larger and larger,and the length of the vorticity holding area becomes longer. Vorticity and velocity fields show different hydrodynamic characteristics in general.