远场辐射热传递在黑体极限上的百倍增强
Dakotah Thompson1, Linxiao Zhu1, Rohith Mittapally1
1Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
Nature
|September 5, 2018
概括
研究人员使用纳米结构证明了辐射热传递 (RHT) 在远场超出了黑体极限. 这一突破可能会影响能量转换和天体物理学.
科学领域:
- 热力学
- 纳米技术
- 光学学
背景情况:
- 辐射热传递 (RHT) 对于各种规模的能量传递至关重要.
- 黑体极限量化最大远场RHT,这是热物理学的基准.
- 超越近场黑体极限已经被证明,但远场超越仍然难以捉摸.
研究的目的:
- 通过实验证明辐射热传递在远场超出黑体极限.
- 为了研究亚波长平面膜之间的RHT.
主要方法:
- 使用集成温度计制造定制的热量计纳米结构.
- 实验测量纳米结构之间的传热速率.
- 实验数据与基于波动电动学的理论计算进行比较.
主要成果:
- 在遥远的场中, 达到超过黑体极限的辐射传热率.
- 在亚波长平面膜之间证明了RHT.
- 观察到的实验热传递率与理论预测非常相符.
结论:
- 远场辐射热传输的黑体极限可以通过工程纳米结构来超越.
- 这些发现为遥远领域的热传输开辟了新的途径.
- 潜在的应用包括能源转化,大气科学和天体物理学方面的进步.
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