缺陷源摆动的对传波

基于流体力学方程组,对长高比Γ=30腔体内混合流体对流中缺陷源摆动的对传波的特性进行了数值模拟.结果发现,当分离比Ψ=-0.6时,缺陷源摆动的对传波的缺陷源由两个对流圈同时被拉长同时被分裂后形成.对传波的存在区间为Dr=0.198,对传波的摆动周期较小并且基本都稳定在T_o=4.8.对传波的摆动幅度较小并且几乎不随着相对瑞利数r变化.当Ψ=-0.2时,对传波的缺陷源下方対流圈轴线与缺陷源移动方向保持一致,没有对传波分支产生.对传波的缺陷源上方存在多个与缺陷源移动方向几乎垂直的対流圈的轴线,存在对传波分支,在对传波分支上出现间歇性的缺陷.从而形成具有单侧缺陷的缺陷源摆动的对传波.对传波的存在区间为Dr=0.16.对传波的摆动周期为To=65.9-85并且随着相对瑞利数的增加而增加.对传波的摆动幅度较大,并且随着相对瑞利数的增加而减小.

Counterpropagating Waves with Oscillation of Defect Source

Based on the equations of hydrodynamics, the counterpropagating wave(CPW) characteristics of the oscillation of the defect source in the binary fluid mixture convection in cavity with aspect ratio Γ =30 were simulated numerically. It is found that at separation ratio Ψ=-0.6, the defect source of CPW with the oscillating defect source is formed by two convective rolls being elongated and split at the same time. The existence interval of CPW is △r=0.198, and the oscillation period of CPW is small and basically stable at To =4.8. The oscillation amplitude of CPW is small and almost does not change with the reduced Rayleigh number r. At Ψ=-0.2, the axis of the convection roll below the defect source is consistent with the moving direction of the defect source, and there is no CPW branch. Above the defect source of CPW, the axes of several convection rolls are almost perpendicular to the moving direction of the defect source movement, and there are CPW branches, in which several intermittent defects exist. Thus, CPW with the oscillating defect source with unilateral defect is formed. The existence interval of CPW is △r=0.16. The oscillation period of CPW is To =65.9-85 and increases with the increase of reduced Rayleigh number. The oscillation amplitude of CPW is large and decreases with the increase of reduced Rayleigh number.