探索辐射颗粒流与快速加热的集中太阳能热能收集和储存的辐射颗粒流
Shin Young Jeong1, Devesh Ranjan1, Zhuomin M Zhang1
1George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, USA.
iScience
|April 11, 2025
概括
辐射通过增加粒子与温度的摩擦来显著改变由重力驱动的颗粒流. 一个新的模型准确地预测了流量温度和热传输,这对于理解辐射颗粒动态至关重要.
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 材料科学 材料科学
背景情况:
- 倾斜平面上的颗粒流在自然和工业过程中很常见.
- 辐射热流对颗粒流动力学和热行为的影响尚未完全理解.
- 了解颗粒流中的热传递对于工艺设计和安全至关重要.
研究的目的:
- 为了研究不同辐射水平对重力驱动的颗粒流的影响.
- 开发和验证辐射颗粒流的热量和质量转移模型.
- 分析颗粒流中的热行为和温度梯度.
主要方法:
- 在不同的辐射热流下 (400-600 kW/m2) 实验测量自由表面速度和温度场.
- 开发一个短暂的,伪二维的热量和质量转移模型.
- 将辐射透率,有效导电和不均的速度配置文件纳入模型.
主要成果:
- 颗粒流动行为受到辐射水平的显著影响,主要是由于温度依赖的粒子摩擦.
- 开发的模型显示了与实验稳定状态自由表面温度的良好相关性 (皮尔森r > 0.9).
- 预测有很大的温度梯度,归因于辐射减弱,速度变化和低导热率.
结论:
- 该研究成功地捕获了辐射倾斜平面颗粒流中的热传输现象.
- 开发的模型为预测这些系统的热行为提供了有价值的工具.
- 这些发现强调了考虑辐射热传递及其对颗粒流动力学影响的重要性.
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