窄方腔软湍流Rayleigh-Bénard热对流中角涡的三维发卡涡结构  

3D hairpin vortex structure of corner vortex of soft turbulent Rayleigh-Bénard convection in narrow square cavity

作　　者：包芸[1] 张义招 徐炜[1] 

机构地区：[1]中山大学力学系,广州510275

出　　处：《计算机辅助工程》2016年第2期48-51,56,共5页Computer Aided Engineering

基　　金：国家自然科学基金(11372362);中央高校基本科研业务费专项资金(14lgjc02)

摘　　要：通过直接数值模拟(Direct Numerical Simulation,DNS)求解三维窄方腔湍流Rayleigh-Bénard(RB)热对流流场,讨论尺度比为1/4的三维窄方腔中的流动.三维方腔流场的流线图和速度场与二维流场一致,都反映出大尺度环流和角涡的软湍流流动特征.进一步观察三维流线图发现,在近底板附近流线的走向并不是沿着大尺度环流的方向.转换三维流线图的观察角度,可明显看到近底板附近流线是螺旋状的,并与角涡相连.分析整个流场的涡旋特征发现,在窄方腔热对流中沿底板棱边区域产生涡对与角涡连接形成三维发卡涡流动的结构.The flow field of 3D turbulent Rayleigh-Bénard（ RB） convection in a narrow square cavity is solved by Direct Numerical Simulation（ DNS）,and the simulation results in the narrow square cavity with 1 /4 scale ratio are discussed. The streamline chart and the velocity field chart of 3D cavity are consistent with those of 2D flow field,which show the soft turbulent flow characteristics of the large scale circulation and the corner vortex. The further observation indicates that the streamline direction near the bottom plate is not along the direction of the large scale circulation. Turning the viewing angle of the 3D streamline chart,it can be obviously seen that the streamlines near bottom plate is spiral and connected to the corner vortex. The analysis on the vortex characteristics of the whole flow field shows that,in the heat convection of the narrow square cavity,there is a 3D hairpin vortex structure generated by the connection of a vortex pair near the bottom plate edge with corner vortex.

关 键 词：三维发卡涡结构 窄方腔 直接数值模拟 Rayleigh-Bénard热对流 

分 类 号：O357.5[理学—流体力学]