• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Water resources research >Numerical study of dynamic Smagorinsky models in large-eddy simulation of the atmospheric boundary layer: Validation in stable and unstable conditions
【24h】

Numerical study of dynamic Smagorinsky models in large-eddy simulation of the atmospheric boundary layer: Validation in stable and unstable conditions

机译：大气边界层大涡模拟中动态Smagorinsky模型的数值研究：在稳定和不稳定条件下的验证

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Large-eddy simulation (LES) of atmospheric boundary layer (ABL) flow is performed over a homogeneous surface with different heat flux forcings. The goal is to test the performance of dynamic subgrid-scale models in a numerical framework and to compare the results with those obtained in a recent field experimental study (HATS (Kleissl et al., 2004)). In the dynamic model the Smagorinsky coefficient c_s is obtained from test filtering and analysis of the resolved large scales during the simulation. In the scale-invariant dynamic model the coefficient is independent of filter scale, and the scale-dependent model does not require this assumption. Both approaches provide realistic results of mean vertical profiles in an unstable boundary layer. The advantages of the scale-dependent model become evident in the simulation of a stable boundary layer and in the velocity and temperature spectra of both stable and unstable cases. To compare numerical results with HATS data, a simulation of the evolution of the ABL during a diurnal cycle is performed. The numerical prediction of c_s from the scale-invariant model is too small, whereas the coefficients obtained from the scale-dependent version of the model are consistent with results from HATS. LES of the ABL using the scale-dependent dynamic model give reliable results for mean profiles and spectra at stable, neutral, and unstable atmospheric stabilities. However, simulations under strongly stable conditions (horizontal filter size divided by Obukhov length > 3.8) display instabilities due to basic flaws in the eddy viscosity closure, no matter how accurately the coefficient is determined.
机译：大气边界层（ABL）流动的大涡模拟（LES）在具有不同热通量强迫的均匀表面上进行。目的是在数值框架中测试动态亚网格规模模型的性能，并将结果与​​最近的现场实验研究（HATS（Kleissl等，2004））相比较。在动态模型中，Smagorinsky系数c_s是通过测试滤波和模拟过程中解析的大尺度分析获得的。在尺度不变动力学模型中，系数与滤波器尺度无关，并且尺度相关模型不需要此假设。两种方法都提供了在不稳定边界层中平均垂直轮廓的真实结果。比例依赖模型的优势在稳定边界层的仿真以及稳定和不稳定情况下的速度和温度谱中都变得显而易见。为了将数值结果与HATS数据进行比较，对昼夜周期中ABL的演变进行了模拟。来自尺度不变模型的c_s的数值预测太小，而从尺度依赖版本的模型获得的系数与HATS的结果一致。使用与比例有关的动力学模型的ABL的LES在稳定，中性和不稳定的大气稳定性下给出了可靠的平均剖面和光谱结果。但是，在强稳定条件下（水平过滤器尺寸除以Obukhov长度> 3.8）的模拟显示，由于涡流粘度封闭中的基本缺陷而导致的不稳定，无论确定系数的精度如何。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号