基于动态混合RANS-LES的近墙模拟的大尖端模拟方法
Michael Tullis1, D Keith Walters1
1Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR 72701, USA.
Entropy (Basel, Switzerland)
|January 8, 2025
概括
这项研究引入了一种新的大型模拟 (LES) 壁处理方法,该方法融合了混合RANS/LES和壁模拟LES (WMLES) 方法. 它有效地模拟近壁流动,提高了不需要复杂的墙壁功能的准确性.
科学领域:
- 计算流体动力学的流体动力学.
- 流建模 流建模
- 流体力学 流体力学 流体力学
背景情况:
- 大尖端模拟 (LES) 在近壁地区的计算成本昂贵.
- 现有的方法,如混合RANS/LES (HRL) 和墙面建模的LES (WMLES) 有其局限性.
- 准确的近壁建模对于解决流流动至关重要.
研究的目的:
- 开发一种新的LES墙壁处理方法,将HRL和WMLES的强度结合起来.
- 为了降低计算成本,同时保持近壁流模拟的准确性.
- 提出一个网格策略,并评估流道流动的性能.
主要方法:
- 采用类似WMLES的流向/横向网格和类似RANS的墙壁正常网格的混合方法.
- 实施一个混合长度模型用于的粘度,局部网格大小受到限制.
- 使用动态混合RANS-LES (DHRL) 框架,轻松地混合RANS和LES地区.
主要成果:
- 拟议的方法合理地预测了流道流动的平均和波动量.
- 与直接数值模拟 (DNS) 数据相比,没有观察到日志层不匹配.
- 该方法需要传统WMLES的网点大约是传统WMLES的两倍,但避免了墙壁功能复杂性.
结论:
- 开发的LES壁处理为近壁流模拟提供了一个可行的替代方案.
- 它有效地平衡计算成本和预测准确性.
- 该方法通过避免分析或数值墙功能来简化实现.
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