无维群通过热相似性:二波现象和信息理论流动模式
1School of Engineering and Technology, The University of New South Wales, Canberra, ACT 2600, Australia.
Entropy (Basel, Switzerland)
|November 24, 2023
概括
这项研究引入了信息理论相似性来分类带有波传播的流动模式. 它定义了新的无维群,以区分亚声波,中声波和超声波流,增强对波浪现象的理解.
科学领域:
- 流体动力学 流体动力学
- 波浪的传播方式
- 信息理论是信息理论.
- 热力学是一种热力学.
背景情况:
- 传统的无维群 (几何,动力学,动态相似性) 对于复杂的流系统是不够的.
- 第一部分引入了基于产量,流速或信息流的相似性.
- 波传播引入了流动模式分类的复杂性.
研究的目的:
- 将相似性的信息理论定义应用于具有波传播的各种流系统.
- 根据信息理论定义新的无维群,用于基于信息理论的流动模式的分类.
- 扩大热相似性的应用,用于分析复杂的流体现象.
主要方法:
- 利用了信息理论上的相似性定义,形成了无维数组的形式 Πinfo=U/c.
- 将这个定义应用于各种波浪现象:声波,爆炸波,压力波,重力波,毛细血管波,惯性波和电磁波.
- 定义并应用了相关的无维数 (马赫,欧拉,弗劳德,罗斯比),并为特定的波型引入了新的组.
主要成果:
- 确定了具有波分散的系统的不同信息理论流动模式 (例如,亚临界/中临界/超临界).
- 声波被分为亚声波/中声波/超声波,重力波/毛囊波/惯性波被分为亚临界波/中声波/超临界波.
- 由于真空的速度,电磁波表现出四种模式 (亚光/中光/超光/超光).
- 分析提供了对各种系统中的摩擦行为,流转和运输的更深入的见解.
结论:
- 信息理论上的相似性定义提供了一个强大的框架来分类波传播的流动模式.
- 新的无维群和扩展的分类 (例如,中等临界,中等发光) 提高了对复杂波动力学的理解.
- 热相似性分析显著推进了对波动驱动流和相关现象的研究.
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