在H形空洞结构内,MHD自由对流与朱尔加热和生成
Md Hasibul Islam1, Riyan Hashem Jamy1, Md Shahneoug Shuvo1
1Department of Mechanical Engineering, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh.
Heliyon
|April 17, 2024
概括
这项研究以计算方式研究H形结构中的水流,分析磁场和朱尔加热效应. 更宽的垂直截面和更厚的水平截面提高了传热性能.
科学领域:
- 流体动力学 流体动力学
- 热传递热量转移的方法
- 计算物理 计算物理
背景情况:
- 在H形外中的自由对流流与各种工程应用有关.
- 外部磁场和内部热量产生 (朱尔加热) 对流体行为的影响需要详细分析.
- 了解不同几何配置下的热性能对于优化传热系统至关重要.
研究的目的:
- 以计算方式研究水在H形空洞结构中的自由对流流和热转移.
- 分析外部磁场 (哈特曼数) 和朱尔加热对流体动力学和热性能的联合影响.
- 检查几何参数,特别是垂直截面的宽度和水平中间截面的厚度对热效率的影响.
主要方法:
- 使用有限元素方法解决纳维埃-斯托克斯方程和热能方程.
- 通过不同的哈特曼数 (0-20),雷利数 (10^3-10^6) 和几何比率 (d/L,t/L) 进行参数计算分析.
- 通过平均努塞尔特数,平均流体温度,总体生成和热性能标准来评估热性能.
主要成果:
- 更宽的垂直截面和更厚的水平截面导致更好的传热,通过更高的平均努塞尔特数和更低的热性能标准来表明.
- 通过增加垂直截面的宽度,观察到最大87.8%的热性能标准减少.
- 对于不同雷利数的哈特曼数和d/L比率的变化,在努塞尔特数中发现了一个有趣的过渡,突出了复杂的流动行为.
结论:
- 几何参数显著影响H型结构的热性能.
- 磁场,朱尔加热和几何之间的相互作用决定了传热的效率.
- 优化垂直和水平截面的尺寸是实现这些系统中卓越传热的关键.
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