A fluid experiment of large-scale topography effect on baroclinic wave flows
A fluid experiment of large-scale topography effect on baroclinic wave flows
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大尺度地形对斜压波流影响的流体实验
DOI：
10.1007/bf02656926
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发表时间：
1992
影响因子：
5.8
通讯作者：
R. Pfeffer
中科院分区：
文献类型：
--
作者：
Guoqing Li;R. Kung;R. Pfeffer
实验研究了地形对热驱动旋转环空中斜压波流的影响，实验数据的Fourier分析和复主分量（CPC）分析表明，由于地形强迫，流场是双峰而不是单一模态。在适当的实验参数下，近热Rossby数ROT =0.1，泰勒数Ta = 2.2 × 107时，大尺度地形在气流中产生低频振荡，并在大气环流中产生类似阻塞的长寿命流型。“阻塞”现象是由地形强迫的行波和准定常波的共振引起的，大尺度地形使波数均匀流转变为波数分散流，分散流具有较低的波数。
The effects of topography on baroclinic wave flows are studied experimentally in a thermally driven rotating annulus of fluid.Fourier analysis and complex principal component (CPC) analysis of the experimental data show that, due to topographic forcing, the flow is bimodal rather than a single mode. Under suitable imposed experimental parameters, near thermal Rossby numberROT =0.1 and Taylor numberTa = 2.2 × 107, the large-scale topography produces low-frequency oscillation in the flow and rather long-lived flow pattern resembling blocking in the atmospheric cir-culation. The ‘blocking’ phenomenon is caused by the resonance of travelling waves and the quasi-stationary waves forced by topography.The large-scale topography transforms wavenumber-homogeneous flows into wavenumber-dispersed flows, and the dispersed flows possess lower wavenumbers.