直接数值模拟一个不稳定的墙壁边界流配置,用于评估大模拟模型
Linus Engelmann1, Josef Hasslberger2, Seung-Jin Baik3
1Fluid Dynamics, Institute for Energy and Materials Processes (EMPI), University of Duisburg-Essen, Carl-Benz-Strasse 199, 47057, Duisburg, Germany. linus.engelmann@uni-due.de.
Scientific reports
|July 11, 2023
概括
一个新的基准案例修改了泰勒-格林带有墙壁和被动标量器来评估流模型的泰勒-格林. 这种围绕墙壁的提供了对直接数值模拟 (DNS) 和大模拟 (LES) 的短暂流动动力学的宝贵见解.
科学领域:
- 计算流体动力学 (CFD) 是一种计算流体动力学.
- 流模拟的流模型.
- 流体力学 流体力学 流体力学
背景情况:
- 直接数值模拟 (DNS) 和大模拟 (LES) 需要强大的基准案例来进行模型评估.
- 标准的泰勒-格林旋缺乏与许多工程应用相关的壁限流物理.
- 在简单几何学中,过渡和不稳定的流体现象对于评估 LES 策略至关重要.
研究的目的:
- 引入一个修改后的泰勒-格林旋基准案例,其中包含墙壁边界条件和被动标量.
- 为了能够研究具有清晰边界和初始条件的过渡静止流.
- 为评估DNS和LES模型提供一个计算可行的案例,模拟热传输.
主要方法:
- 修改标准的泰勒-格林,在一个方向引入一个无滑边界条件.
- 包括一个被动的标量体从墙壁传输到流体.
- 进行详细的融合研究,使用四个精制网格 (精制2的因素) 来进行DNS/LES计算.
主要成果:
- 汇聚的二次统计得到了[公式:参见文本]的无维时间.
- 修改后的案例显示了具有挑战性的近壁流动动力学,这种动力学在标准的泰勒-格林中并不存在.
- 结果的不确定性超出[公式:参见文本]被归因于流动的不稳定,混乱的性质.
结论:
- 拟议的围绕墙壁的泰勒-格林旋作为DNS和LES的有价值的基准.
- 它有效地捕捉了与流模型评估相关的短暂流动物理和近壁动态.
- 该案例易于设置,计算效率高,并且不需要超越标准DNS/LES的额外建模.
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