A two-fluid single-column model of turbulent shallow convection. Part 1: Turbulence equations in the multifluid framework
A two-fluid single-column model of turbulent shallow convection. Part 1: Turbulence equations in the multifluid framework
复制标题
湍流浅对流的双流体单柱模型。
DOI：
10.1002/qj.4366
复制
发表时间：
2022
影响因子：
8.9
通讯作者：
Thuburn J
中科院分区：
文献类型：
--
作者：
Thuburn J
从可压缩欧拉方程（或气象学中常用的任何近似方程组）通过条件滤波导出多流体方程。它们有可能为改进积云对流及其与边界层和数值模式中大尺度流的耦合提供基础。本文推导了多流体框架中的子过滤尺度湍流二阶矩的预报方程，沿着对它们进行了一定的系统简化，从而提供了一个著名的梅洛尔和山田湍流闭合等级的多流体模拟。除了能够更准确地计算子过滤尺度通量以及子过滤尺度变化对云分数、液态水和浮力的影响外，二阶矩信息还可以用于获得更准确的卷吸和消散参数化。本文导出的湍流方程的一个子集被用于第2部分中描述的双流体单柱模型中，并应用于第3部分中的浅积云情况的模拟。
The multifluid equations are derived from the compressible Euler equations (or any of the usual approximate equation sets used in meteorology) by conditional filtering. They have the potential to provide the basis for an improved representation of cumulus convection and its coupling to the boundary layer and larger scale flow in numerical models. The present article derives the prognostic equations for subfilter‐scale turbulent second moments in the multifluid framework, along with certain systematic simplifications of them, thus providing a multifluid analogue of the well‐known Mellor and Yamada hierarchy of turbulence closures. As well as enabling a more accurate calculation of subfilter‐scale fluxes and the effects of subfilter‐scale variability on cloud fraction, liquid water, and buoyancy, the second moment information can be used to obtain a more accurate parameterization of entrainment and detrainment. A subset of the turbulence equations derived here is employed in the two‐fluid single‐column model described in Part 2 and applied to the simulation of shallow cumulus cases in Part 3.