在环状细胞中对流雷利-贝纳德对流的流体结构和动态进行实验研究
Ji-Li Zheng1, Yu-Lu Liu1,2
1Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, China.
Physical review. E
|July 19, 2023
概括
环状细胞中的流雷利-贝纳德对流会表现出不同的四极和六极状态. 倾斜细胞诱导静止和移动波状态之间的过渡,提供了对对流动力学的见解.
科学领域:
- 流体动力学 流体动力学
- 热传递热量转移的方法
- 流是什么?流是什么?流是什么?
背景情况:
- 流雷利-贝纳德对流是传热和流体动力学中的一个基本过程.
- 了解狭窄几何体中的流体结构和动态对于各种应用至关重要.
- 具有特定半径和尺寸比的环状细胞具有独特的挑战和现象.
研究的目的:
- 实验性地研究一个环状细胞中流雷利-贝纳德对流的流结构和动态.
- 描述不同的多滚动静止波状态及其过渡.
- 探索细胞倾斜对对流动动力学和波浪行为的影响.
主要方法:
- 使用半径比为0.5的环状细胞,面积比为4.4.
- 采用多热探测方法进行温度配置测量.
- 应用粒子图像速度计 (PIV) 用于速度场分析.
主要成果:
- 观察到两个不同的多滚动静止波状态:四极状态 (QS) 具有四个滚动和六极状态 (SS) 具有六个滚动.
- 确定雷诺兹数 (Re) 与雷利数 (Ra) 的不同缩放指数:QS的0.56和SS的0.41.
- 发现将细胞倾斜1°会使静止波变为移动波,在高Ra时观察到从SS到QS的过渡.
结论:
- 这项研究揭示了环状几何体内的流对流中明显的流动行为和状态过渡.
- 观察到的静止和移动波状态之间的过渡,以及QS和SS之间的过渡,突出了复杂的动态.
- 这些发现有助于更深入地了解与旋转对称的对流流及其稳定性.
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