三维声学流:弱相对强:弱相对强
E A Kochurin1,2, E A Kuznetsov2,3,4
1<a href="https://ror.org/051jjt714">Institute of Electrophysics</a>, Ural Branch of RAS, 620016, Yekaterinburg, Russia.
Physical review letters
|December 3, 2024
概括
直接的数值模拟显示了扎哈罗夫-萨格迪耶夫频谱在声学流中,即使没有分散. 在非分散情况中增加的非线性效应会导致随机冲击和卡多姆切夫-佩特维亚什维利频谱.
科学领域:
- 流体动力学 流体动力学
- 血物理学的等离子体物理学
- 波浪现象是一种波浪现象.
背景情况:
- 声学流描述了复杂的波浪相互作用.
- 了解乱光谱是流体和等离子体物理学中的关键.
- 以前的研究集中在分散效应上.
研究的目的:
- 为了研究弱态和强态中的声学流频谱.
- 在非分散 (ND) 情况下探索扎哈罗夫-萨格迪耶夫光谱.
- 分析过渡到冲击主导的流.
主要方法:
- 三维声学流的直接数值模拟 (DNS).
- 波数 (k) 空间光谱的分析.
- 检查非线性和分散/衍射效应.
主要成果:
- 扎哈罗夫-萨格迪耶夫光谱 (k^{-3/2}) 在弱流中被观察到,包括ND病例.
- 狭窄的形喷射伴随着这些光谱.
- 在ND的情况下,主导的非线性效应导致冲击形成和卡多姆茨耶夫-佩特维亚什维利光谱.
结论:
- 扎哈罗夫-萨格迪耶夫光谱很强大,即使没有分散,也存在.
- 在ND的情况下,在强烈的非线性驾驶下,声波流转变为随机冲击.
- 这些发现有助于理解非线性波现象和流.
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