Resolved Versus Parametrized Boundary-Layer Plumes. Part II: Continuous Formulations of Mixing Rates for Mass-Flux Schemes
Resolved Versus Parametrized Boundary-Layer Plumes. Part II: Continuous Formulations of Mixing Rates for Mass-Flux Schemes
复制标题
解析与参数化边界层羽流。
DOI：
10.1007/s10546-010-9478-z
复制
发表时间：
2010
影响因子：
4.3
通讯作者：
A. Jam
中科院分区：
文献类型：
--
作者：
C. Rio;F. Hourdin;F. Couvreux;A. Jam
对流边界层大涡模拟中相干结构的条件采样（Couvreux et al. Boundary-layer Meteorol 134：441-458，2010）被用于提出和评估质量通量方案的分数夹带率和分离率的公式。所提出的配方是基于物理的，并且从云的表面到顶部是连续的。卷吸与上升气流的垂直速度发散有关，而消散则取决于热垂直速度、浮力和平均羽流与环境之间的湿度对比。所提出的配方首先直接评估模拟的浅云。然后，他们进行了测试，在单柱模拟与热羽流模型，质量通量表示的边界层热气流。
The conditional sampling of coherent structures in large-eddy simulations of the convective boundary layer (Couvreux et al. Boundary-layer Meteorol 134:441–458, 2010) is used to propose and evaluate formulations of fractional entrainment and detrainment rates for mass-flux schemes. The proposed formulations are physically-based and continuous from the surface to the top of clouds. Entrainment is related to the updraft vertical velocity divergence, while detrainment depends on the thermal vertical velocity, on buoyancy and on the moisture contrast between the mean plume and its environment. The proposed formulations are first directly evaluated in simulations of shallow clouds. They are then tested in single-column simulations with the thermal plume model, a mass-flux representation of boundary-layer thermals.