科尔摩戈罗夫流与浮力驱动的泡流中的伪流共存
Vikash Pandey1,2, Dhrubaditya Mitra2, Prasad Perlekar1
1Tata Institute of Fundamental Research, Gopanpally, Hyderabad 500046, India.
Physical review letters
|September 29, 2023
概括
浮力驱动的泡流在高利略数时呈现科尔摩戈罗夫缩放,小尺度上占据主导地位的伪流. 这项研究阐明了气泡流体动力学中的能量转移.
科学领域:
- 流体动力学 流体动力学
- 流研究 流研究
- 多相流程 多相流程
背景情况:
- 浮力驱动的泡流在工业和自然过程中很常见.
- 了解它们的光谱特性和能量转移对于准确的建模至关重要.
- 以前的研究已经探讨了泡流动流的各个方面,但需要进行全面的光谱分析.
研究的目的:
- 为了研究浮力驱动的泡流的光谱特性.
- 确定这些流动中的关键能量转移机制.
- 为了确定控制速度功率光谱的缩放规律.
主要方法:
- 使用高分辨率的数值模拟来建模泡流.
- 同质流的现象学被用来分析模拟数据.
- 速度功率光谱被计算在各种尺度上.
主要成果:
- 在高的利莱数下,速度功率光谱在气泡直径和散射尺度之间遵循科尔摩戈罗夫缩放 (指数 -5/3).
- 这种缩放表明,在一系列流旋中,能量的转移效率高.
- 对于比散射尺度 (η) 小的尺度,流量表现出伪流特征.
结论:
- 这项研究确立了浮力,泡大小和泡流中的乱缩放之间的明确联系.
- 科尔摩戈罗夫缩放是这些流程中大量尺度的相关描述符.
- 伪流支配着最小规模的动态,与更大规模的能量级联不同.
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