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两个自相似的雷诺兹应力传输模型具有异型旋粘度
Brandon E Morgan1, Kevin Ferguson1, Britton J Olson1
1Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
Physical review. E
|December 20, 2023
概括
使用全雷诺兹应力传输 (RST) 的新雷诺兹平均纳维埃-斯托克斯模型准确模拟乱的混合层. 这些模型在各种流动场景中捕捉了雷利-泰勒和凯尔文-赫尔姆霍尔茨不稳定的基本物理.
科学领域:
- 流体动力学 流体动力学
- 计算物理 计算物理
- 流建模 流建模
背景情况:
- 雷诺兹-平均纳维尔-斯托克斯 (RANS) 模型对于模拟流非常重要.
- 现有的模型往往难以准确地捕捉复杂流程中的异型流效应.
- 为了提高预测能力,需要扩展k-2L-a-C和k-φ-L-a-C模型.
研究的目的:
- 开发和验证新的RANS模型,包括完全的雷诺兹应力传输 (RST) 和张力旋粘度.
- 调查这些模型在规范混合层中复制自相似生长的能力.
- 在现实和复杂的流量配置中评估模型性能.
主要方法:
- 为现有RANS模型开发RST扩展.
- 应用自我相似性分析来限制模型系数.
- 雷利-泰勒和凯尔文-赫尔姆霍尔茨不稳定的一维和二维模拟.
- 模拟一个倾斜的火箭装置实验和一个冲击加速的流补丁.
主要成果:
- 模型成功地复制了RT和KH混合层的自相似增长率和异质性.
- RST对于质量捕捉冲击加速流斑块的生长至关重要.
- 与Boussinesq近似相比,无异型的粘度显著改善了倾斜火箭平台问题的结果.
结论:
- 拟议的基于RST的RANS模型为模拟流混合现象提供了更高的准确性.
- 这些模型为预测涉及RT和KH不稳定的复杂流提供了更强大的框架.
- 这些发现突出了RST和异型粘度在先进的流模型中的重要性.
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