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Updated: Jan 17, 2026
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The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
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尺度流量传输模型用于自相似的流混合
1Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
Physical review. E
|September 16, 2025
概括
新的标量流量传输 (SFT) 模型优于流混合的标准梯度扩散近似. 这些先进的模型更好地捕捉复杂的现象,如反梯度运输和异性质物质运输.
科学领域:
- 流体动力学 流体动力学
- 计算科学 计算科学
- 流模型 流模型
背景情况:
- 标准梯度扩散近似用于在雷诺兹-平均纳维尔-斯托克斯 (RANS) 模型中关闭动荡物种流.
- 这种方法在捕捉复杂的乱混合现象方面存在局限性,例如反梯度运输.
- 对于复杂的应用,需要使用替代方法,比如使用模拟运输方程来计算流扩散率.
研究的目的:
- 开发和评估两个新的标量流量传输 (SFT) 模型.
- 在动荡混合场景中,将SFT模型的性能与基于梯度扩散的模型进行比较.
- 对复杂的运输现象研究证券交易交易模型的好处,包括混合方法.
主要方法:
- 开发两个不同的标量流量传输 (SFT) 模型.
- 为拟议的证券交易型号推导自我相似性约束.
- 在1D和2D流混合问题中对SFT模型与梯度扩散模型进行评估.
主要成果:
- 与梯度扩散模型相比,新的SFT模型表现出更高的性能.
- 在涉及快速加速逆转和异型物质运输的模拟中,SFT模型表现出色.
- 混合-SFT方法比运输质量流量而不是标量流量的模型有所改善.
结论:
- 尺度流量传输模型在复杂的流混合中比标准梯度扩散近似提供了显著的优势.
- 开发的SFT模型准确地捕捉了像反梯度运输和异型运输这样的现象.
- 即使是混合的SFT方法也为动荡的物种流动提供了增强的预测能力.
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