Stability of Thermal Convection in a Rapidly Rotating Sphere.
Stability of Thermal Convection in a Rapidly Rotating Sphere.
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DOI：
10.1143/jpsj.63.2964
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发表时间：
1994-08
影响因子：
1.7
通讯作者：
S. Kida
中科院分区：
文献类型：
--
作者：
S. Kida
采用奇异摄动法分析了旋转球体内自重力和内热源驱动的热对流在大泰勒数Ta下的线性稳定性。位于径向方向的中性扰动通常从该方向倾斜。这种倾斜扰动的径向结构采用高斯形式，在 O ( T a -1/12 ) 的长度尺度上扩展。随着倾斜角减小，扰动的局部性变弱。在均匀热源和线性重力的特殊情况下，证明了临界瑞利数R a c * 应该通过这种具有消失倾斜角的扰动来获得(F. H. Busse, J. Fluid Mech. 44 (1970) 441)。然而，由于没有倾斜的干扰不能定位在径向方向上，因此该临界瑞利数是标称的。当瑞利数略大于临界值 (R a * - Ra c * = O ( T a -1/9 )) 时，扰动仅轻微倾斜（O ( T a -1/18 )）并在长度尺度上传播......
Linear stability of thermal convection driven by self-gravity and internal heat source in a rotating sphere is analyzed by a singular perturbation method at large Taylor number T a . The neutral disturbance localized in the radial direction generally tilts from that direction. The radial structure of such oblique disturbance takes a Gaussian form spreading over length-scale of O ( T a -1/12 ). The localness of disturbance becomes weaker as the tilt angle decreases. In the special case of uniform heat source and linear gravity force it is proved that the critical Rayleigh number R a c * should be attained by such disturbances that have vanishing tilt angle (F. H. Busse, J. Fluid Mech. 44 (1970) 441). Since, however, no disturbance without tilting can be localized in the radial direction, this critical Rayleigh number is nominal. At the Rayleigh number slightly greater than the critical ( R a * - R a c * = O ( T a -1/9 )), the disturbance tilts only slightly (by O ( T a -1/18 )) and spreads over length-scal...