Turbulent acoustic streaming with large Reynolds number and its effects on the thermal conduction and mixing

大雷诺数湍流声流及其对热传导和混合的影响

• 批准号: 12450072
• 负责人: ICHIJO Makoto
• 金额: $ 3.71万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450072/
• 关键词: Acoustic streaming; Nonlinear acoustics; Resonant oscillation; High Reynolds number flow; Shock wave; Bifurcation; Turbulence; Vortex; 高レイノルズ数; 定在波; 非線形音響; 熱輸送; 物質混合

Acoustic streaming is a mean mass flow induced by the nonlinear effect of acoustic waves. It has been expected that turbulent acoustic streaming can enhance the thermal conduction, mixing, and stirring of materials in vessels. The lack of a full understanding of the physical characters of acoustic streaming with large Reynolds number prevents the development of such technologies. In the present study, we have theoretically and numerically investigated acoustic streaming with large Reynolds number induced by large amplitude resonant gas oscillations in a closed tube. The method of theoretical analysis is based on the singular perturbation. The numerical methods are a high-resolution upwind TVD scheme and a standard MAC method.The main results can be summarized as follows:(1) We have examined the one-dimensional oscillations, which is of the most fundamental importance in our problem. We have shown that the amplitude modulation occurs in an initial transient state, and that the temperature in the gas is raised by the heat production due to the shock waves.(2) The streamlines of acoustic streaming are distorted by the shock waves.(3) A vortex doubling bifurcation has been demonstrated by a large scale numerical simulation.(4) We have numerically shown that a bifurcation of steady state solution of acoustic streaming in a 2-dimensional box creates a pair of steady state solutions, which lose the symmetry of the original solution. The streaming motion after the bifurcation is a large scale circulatory motion in the box. This means that acoustic streaming with large Reynolds number may be useful for thermal conduction, mixing, and stirring of materials in vessels.

声流是由声波的非线性效应引起的平均质量流。人们一直期望湍流声流可以增强容器中材料的热传导、混合和搅拌。由于对大雷诺数声流的物理特性认识不足，阻碍了声流技术的发展。在本研究中，我们从理论上和数值上研究了大雷诺数下封闭管道中气体大振幅共振振荡引起的声流。理论分析的方法是基于奇异摄动。数值方法为高分辨率迎风TVD格式和标准MAC方法，主要结果如下：（1）我们研究了问题中最基本的一维振荡。我们已经表明，振幅调制发生在初始的瞬态，并在气体中的温度升高的热产生由于冲击波。(2)声流的流线被激波扭曲。(3)通过大尺度数值模拟，证实了涡倍增分叉现象。(4)数值计算表明，二维箱中声流稳态解的分叉产生一对稳态解，这对稳态解失去了原解的对称性。分叉后的流动运动是一个大尺度的循环运动。这意味着具有大雷诺数的声流可用于容器中材料的热传导、混合和搅拌。

项目成果

Makoto Ichijo: "Vortical structures related to wall pressure structure fluctuations in a turbulent boundary layer"Turbulence and Shear flow Phenomena(proceedings of Second International Symposium KTH, Stockholm June 2001). Vol.3. 221-226

Makoto Ichijo：“与湍流边界层中的壁压力结构波动相关的涡流结构”湍流和剪切流现象（KTH 第二届国际研讨会论文集，斯德哥尔摩，2001 年 6 月）。

Makoto Ichijo: "Vortical structures related to wall pressure fluctuations in a turbulent boundary layer"Turbulence and Shear flow Phenomena (Proceedings of Second International Symposium KTK Stockholm, June 2001). 3. 221-226 (2001)

Makoto Ichijo：“与湍流边界层中的壁压力波动相关的涡流结构”湍流和剪切流现象（第二届国际研讨会 KTK 斯德哥尔摩会议记录，2001 年 6 月）。

Makoto Ichijo: "Vortical structures related to wall pressure structure fluctuations in a turbulent boundary layer"Turbulence and Shear flow Phenomena (Proceedings of Second International Symposium, KTH, Stockholm, June 2001). Vol.3. 221-226

Makoto Ichijo：“与湍流边界层中的壁压力结构波动相关的涡流结构”湍流和剪切流现象（第二届国际研讨会论文集，KTH，斯德哥尔摩，2001 年 6 月）。