The structure of energy conserving low-order models
The structure of energy conserving low-order models
复制标题
节能低阶模型的结构
DOI：
10.1063/1.869883
复制
发表时间：
1999
影响因子：
4.6
通讯作者：
Christopher Tong
中科院分区：
文献类型：
--
作者：
A. Gluhovsky;Christopher Tong
发展物理健全的低阶模型在流体动力学的一般原则进行了讨论。它示出，低阶模型与能量守恒性质的原始方程中出现的各种重要的问题（瑞利-贝纳德对流，旋转流体，磁流体动力学对流）可以提出的形式耦合的三模系统在力学中称为沃尔泰拉陀螺仪（加上条款描述强迫和摩擦）。当这些模型通过增加近似阶数或增加新的物理机制进行扩展时，它们仍然具有耦合陀螺仪的结构。相反，当低阶模型不能转换成耦合陀螺仪时，这可能表明它的守恒性质应该受到质疑。例如，虽然广泛使用的（在对流研究中）霍华德-克里希那穆提模型[J.流体力学。170，385（1986）]不是能量守恒的，也没有陀螺仪的形式，它的简单扩展到耦合陀螺仪系统具有......
General principles for developing physically sound low-order models in fluid dynamics are discussed. It is shown that low-order models with energy conserving properties of the original equations that arise in various important problems (Rayleigh–Benard convection, rotating fluid, magnetohydrodynamic convection) may be presented in the form of coupled three-mode systems known in mechanics as Volterra gyrostats (plus terms describing forcing and friction). When these models are expanded by increasing the order of approximation or by adding new physical mechanisms, they still have the structure of coupled gyrostats. Conversely, when a low-order model cannot be transformed into coupled gyrostats, this may indicate that its conservation properties should be questioned. For instance, while the widely used (in convection studies) Howard–Krishnamurti model [J. Fluid Mech. 170, 385 (1986)] is not energy conserving and does not have a gyrostatic form, its simple extension to a system of coupled gyrostats possesses ...