模型规模乱大气边界层流动的大模拟
1NIST Director's Postdoctoral Fellow, Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899.
概括
大模拟 (LES) 准确地代表了用于结构工程的大气边界层 (ABL) 流统计数据. 虽然简单的模型显示了地面附近的局限性,但它们有效地捕捉了关键的流体物理.
科学领域:
- 流体动力学 流体动力学
- 大气科学 大气科学
- 计算工程 计算工程
背景情况:
- 大气边界层 (ABL) 流动对于结构工程应用至关重要.
- 精确模拟ABL流对于可靠的结构设计至关重要.
- 之前的研究强调了对ABL流量的验证模拟方法的需要.
研究的目的:
- 为了执行模型缩放的,中性分层的ABL流量的大模拟 (LES).
- 为了分析模拟ABL流的统计性质.
- 评估LES与简单子网尺度 (SGS) 和结构工程墙壁模型的适用性.
主要方法:
- 在中性分层ABL流中使用大模拟 (LES).
- 使用一-k-方程旋模型进行子电网尺度 (SGS) 运动.
- 实现了墙壁剪切模型来表示地面效应.
主要成果:
- 平均流向速度概况呈现了对数趋势,由于SGS模型的限制,在地面附近有轻微的偏差.
- 动荡秒钟时刻准确地反映了潜在的物理过程.
- 速度组成部分的光谱和空间连贯性与既定的理论表达式保持一致.
结论:
- 大模拟 (LES) 与基本的SGS和墙壁模型有效地代表了ABL流统计数据.
- 这些模拟适用于结构工程应用,但在准确预测地面附近的平均速度方面存在明显的局限性.
- 这项研究验证了LES作为分析工程环境中的ABL流量的强大工具.
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