热传输到颗粒流的微机械起源
Xintong Zhang1, Sarath Adapa1, Tianshi Feng1
1Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093, USA.
Physical review. E
|May 17, 2024
概括
这项研究用一种新的光热技术量化颗粒流中的传热电阻. 与静态状态相比,流动颗粒材料具有较高的近壁电阻和较低的散热导电性.
科学领域:
- 物理 物理学 物理
- 工程 工程师 工程师 工程师
- 材料科学 是一种材料科学.
背景情况:
- 由于在隔离近壁和散装电阻方面存在挑战,对颗粒流中的热传输的了解很少.
- 现有的实验方法缺乏分辨率来区分这些贡献.
研究的目的:
- 开发和应用一种技术,单独量化颗粒流的近壁和散装区域的热电阻.
- 为了研究流量对传热特性的影响.
主要方法:
- 利用频率调制的光热技术来探测热特性.
- 采用离散元件方法 (DEM) 模拟进行分析.
- 在流动状态和静止颗粒状状态下比较热传递.
主要成果:
- 在近壁和散装区域量化显著的热电阻.
- 与静止相比,在流动的颗粒状状态中观察到近壁阻力增加.
- 在流动的颗粒状状态下测量了散热导电率的降低.
结论:
- 频率调制光热技术成功地将颗粒流中的热电阻分离出来.
- 颗粒流中的粒子扩散解释了观察到的近壁电阻的增加.
- 流量显著改变颗粒床内的传热机制.
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