在泡热对流的热对流中,双极流向单极流的转换
Rajaram Lakkaraju1, Dinesh Kumar Chandraker2, Gautam Biswas3
1TuRbulent Interfaces And Dispersion (TRIAD) group, Department of Mechanical Engineering, <a href="https://ror.org/03w5sq511">Indian Institute of Technology Kharagpur</a>, West Bengal 721302, India.
Physical review. E
|December 18, 2024
概括
蒸汽泡之间的相互作用显著影响热量传递. 气泡分离距离和雅各布数 (Ja) 影响流量模式和热传输,气泡对流比经典热对流更强.
科学领域:
- 流体动力学 流体动力学
- 热传递热量转移的方法
- 阶段变化现象 变相现象
背景情况:
- 蒸汽泡的水力动力学和热相互作用对热传输至关重要.
- 了解这些相互作用是优化沸热传递过程的关键.
研究的目的:
- 以数值研究雅各布数 (Ja) 和气泡分离距离 (d) 对蒸汽泡相互作用的影响.
- 分析由此产生的流量特性和热传输机制.
主要方法:
- 在2D方形外中对和蒸汽泡进行数值模拟.
- 控制加热和冷却以模拟100°C的沸.
- 雅各布数 (Ja) 和气泡分离距离 (d) 的系统变化.
主要成果:
- 流动稳定性取决于泡分离距离,从二极管过渡到三极管模式.
- 水力动力学不稳定性在关键的雅各布数 (Ja ≈ 2.8) 时出现,在高的Ja时诱导断模式.
- 在低Ja时,相变热传输占主导地位,而在高Ja时,对流术语是显著的.
结论:
- 气泡相互作用显著改变了流动动力学和热传输.
- 与经典的热对流相比,泡对流显示出优越的整体热传输.
- 研究结果为优化沸系统中的热传递提供了洞察力.
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