Three-dimensional simulations of convection in layers with tilted rotation vectors
Three-dimensional simulations of convection in layers with tilted rotation vectors
复制标题
具有倾斜旋转矢量的层内对流的三维模拟
DOI：
10.1017/s0022112083000051
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发表时间：
1983
影响因子：
3.7
通讯作者：
R. Somerville
中科院分区：
文献类型：
--
作者：
D. Hathaway;R. Somerville
对旋转层进行了三维和时间相关的热对流数值模拟，其中旋转矢量从垂直方向倾斜以表示不同的纬度。旋转矢量的垂直分量产生狭窄的对流单元和减少的热通量。随着旋转矢量的垂直分量在低纬度地区减少，垂直热通量增加。旋转矢量的水平分量在对流运动中产生显着的变化。它在南北方向上拉长了对流单元。它还倾向于以产生大规模环流的方式将向上运动转向西方，将向下运动转向东部。该环流在该层的上半部分指向西方并朝向两极，在下半部分指向东方并朝向赤道。由于该层底部较温暖，因此这种环流还携带向赤道的热通量。当旋转矢量从垂直方向倾斜时，角动量总是向下并朝向赤道传输。对于快速旋转的层，压力场的变化方式往往会平衡垂直运动上的科里奥利力。当旋转速率在有限的旋转速率范围内增加时，这导致垂直热通量增加。
Three-dimensional and time-dependent numerical simulations of thermal convection are carried out for rotating layers in which the rotation vector is tilted from the vertical to represent various latitudes. The vertical component of the rotation vector produces narrow convection cells and a reduced heat flux. As this vertical component of the rotation vector diminishes in the lower latitudes, the vertical heat flux increases. The horizontal component of the rotation vector produces striking changes in the convective motions. It elongates the convection cells in a north–south direction. It also tends to turn upward motions to the west and downward motions to the east in a manner that produces a large-scale circulation. This circulation is directed to the west and towards the poles in the upper half of the layer and to the east and towards the equator in the bottom half. Since the layer is warmer on the bottom this circulation also carries an equatorward flux of heat. When the rotation vector is tilted from the vertical, angular momentum is always transported downwards and toward the equator. For rapidly rotating layers, the pressure field changes in a manner that tends to balance the Coriolis force on vertical motions. This results in an increase in the vertical heat flux as the rotation rate increases through a limited range of rotation rates.