A comparison of laboratory measurements and numerical simulations of baroclinic wave flows in a rotating cylindrical annulus
A comparison of laboratory measurements and numerical simulations of baroclinic wave flows in a rotating cylindrical annulus
复制标题
旋转圆柱环内斜压波流的实验室测量和数值模拟的比较
DOI：
--
复制
发表时间：
1985
期刊：
影响因子：
--
通讯作者：
R. M. Small
中科院分区：
文献类型：
--
作者：
By P. Hignett;A. A. White;R. D. Carter;W. D. N. Jackson;R. M. Small
将旋转环空流动的实验室测量结果与相应的数值模型模拟结果进行了定量和定性的比较。使用了两个尺寸相似但仪器不同的实验室环。其中一个包含用于温度测量的热电偶阵列：另一个不包含传感器阵列，但工作流体中加入了微小的中性浮珠(直径600 mm)，从而能够测量水平速度场。每个环空都有一个与工作流体接触的坚硬的绝缘盖子。数值模型是基于N-S方程的Boussinesq液体斜压流动的有限差分格式。虽然大气和实验室环空都是旋转的斜压流体系统，但作用在环空中的强迫过程比作用在大气中的强迫过程简单得多，并且可以用已建立的公式准确地表示：在很大范围的条件下，不需要对次网格尺度的动力和非绝热过程进行参数化。因此，将数值模型结果与实验室测量结果相比较，能够在一定程度上验证旋转斜压流动数值模型的显式动力学公式，这将是使用大气数据很难实现的，如果不是不可能的话。对定常波流进行了详细的定量比较，发现温度场和水平流场的主要特征很好地吻合，尽管在总热流密度上发现了显著的差异。通过考察数值模式再现实验室系统主要流动类型和现象的能力，进行了定性比较。描述了非传递性、滞后性、波数跃迁、振幅抖动和弱结构抖动的数值模拟。最后，对进一步的比较研究提出了几点建议。
Quantitative and qualitative comparisons are made between laboratory measurements of rotating annulus flows and corresponding numerical model simulations. Two laboratory annuli, of similar dimensions but differing in instrumentation, are used. One contains a thermocouple array for temperature measurement: the other contains no sensor array but the working fluid is seeded with minute neutrally buoyant beads (600 mm diameter) which enable the horizontal velocity field to be measured. Each annulus has a rigid insulating lid in contact with the working fluid. the numerical model is a finite difference formulation based on the Navier-Stokes equations for baroclinic flow of a Boussinesq liquid. Although the atmosphere and the laboratory annulus are both rotating baroclinic fluid systems, the forcing processes acting in the annulus are much simpler than those acting in the atmosphere, and may be accurately represented by established formulae: under a wide range of conditions no parametrizations of subgrid-scale dynamical and diabatic processes are required. Comparison of numerical model results with laboratory measurements therefore enables the explicit dynamical formulation of numerical models of rotating, baroclinic flow to be verified to an extent which would be very difficult, if not impossible, to achieve using atmospheric data. Detailed quantitative comparisons for a steady wave flow reveal good agreement for major features of the temperature and horizontal flow fields, although a significant discrepancy in total heat flux is found. Qualitative comparisons are made by investigating the ability of the numerical model to reproduce the main flow types and phenomena of the laboratory system. Numerical simulations of intransitivity, hysteresis, wavenumber transitions, amplitude vacillation and a weak structural vacillation are described. Several suggestions for further comparative studies are made in conclusion.