The turbulent interaction among scale-separated gravity waves and between gravity waves and synoptic-scale flow

尺度分离重力波之间以及重力波与天气尺度流之间的湍流相互作用

• 批准号: 137502438
• 负责人: Professor Dr. Ulrich Achatz
• 金额: --
• 依托单位: Faculty of Aerospace Engineering
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/137502438?language=en
• 关键词: turbulent; interaction; among; scale; separated

Gravity waves (GWs) play an important role in the dynamics of the atmosphere. Even the highest-resolution weather-forecast models, however, cannot resolve the entire range of gravity waves. The complexity of the resulting parameterization problem is increased by the fact that, where GWs are affected by breaking, wave-turbulence interactions are important. The project intends to address the parameterization of GW emission from synoptic-scale flow, their propagation and breaking by a hierarchical approach. (1) Data from high-resolution direct numerical simulations (DNS) of turbulence from breaking GWs will be used in the development of an implicit sub-grid scale (SGS) turbulence parameterization. These DNS will describe typical paradigms of GW dissipation by focusing on the initial perturbations most effective in leading to wave breaking. (2) A ray-tracing algorithm for the interaction of small-scale GWs with large-scale GWs, an important aspect of GW dynamics, shall be developed and validated against data from large-eddy simulations (LES) of typical cases. (3) Also using LES, the emission of GWs from synoptic-scale flow in a rotating annulus shall be studied. The results shall be compared with those from the laboratory experiment.

重力波在大气动力学中起着重要的作用。然而，即使是最高分辨率的天气预报模型，也无法解析整个重力波范围。由此产生的参数化问题的复杂性增加的事实，即，在GWs的破碎，波湍流相互作用的影响是很重要的。该项目打算解决GW排放的参数化从天气尺度流，他们的传播和打破的层次方法。(1)从高分辨率的直接数值模拟（DNS）的数据湍流从打破GWs将被用于开发一个隐式的亚网格尺度（SGS）湍流参数化。这些DNS将描述GW耗散的典型范例，重点放在最有效的初始扰动导致波破碎。(2)小尺度GW与大尺度GW相互作用的射线追踪算法，GW动力学的一个重要方面，应根据典型情况的大涡模拟（LES）数据开发和验证。(3)还应使用大涡模拟研究旋转环中天气尺度流的全球Ws排放。应将结果与实验室试验的结果进行比较。