混合流体对流中具有间歇性缺陷的缺陷源摆动的对传波

A counter propagating wave with undulation of defect source with intermittent defects in binary fluid convection

通过数值模拟,研究了长高比Γ_x=40和分离比ψ-=2.0时有间歇性缺陷的缺陷源摆动的对传波。研究表明:对于给定的相对瑞利数r,在缺陷源摆动的对传波中,缺陷源做"S"型曲线摆动,缺陷源两侧行波分支上存在间歇性缺陷,行波分支上的缺陷数量不固定;随相对瑞利数r增加,缺陷源沿腔体水平方向的摆动振幅不断减小,缺陷源两侧行波分支上的缺陷数量呈减少局势,缺陷源初始摆动方向由向左变为向右;垂直流速最大值δw_(max)和下壁面努塞尔数Nu-1是相对瑞利数r的函数,并给出了它们随着相对瑞利数r的变化关系式。

Using the numerical simulations of the two-dimensional full equations of hydrodynamics,a counter propagating wave with undulation of defect source with intermittent defects in binary fluid convection in a rectangular cell with a large-aspect-ratioΓx=40and separation ratioψ=-0.20is studied.It is found that for a given reduced Rayleigh number r,the defect source moves with'S'type curve,intermittent defects exist on the branch of the traveling wave on both sides of the defect source,and the number of defects is not fixed.With the increase of reduced Rayleigh number r,the amplitude of undulation of the defect source decreases along the horizontal direction of the cavity,the number of defects on the branch of the traveling wave on both sides of the defect source is also reduced,and the initial undulation direction of the defect source is changed from left to right.The maximum vertical velocityδwmaxand Nusselt number Nu-1 along the lower wall are a function of reduced Rayleigh number r,and formulas for computing the maximum vertical velocity and Nusselt number along the lower wall with r are proposed also.