时间调节的近场辐射热传递
1Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, CA 94305.
概括
近场辐射热传递的时间调制可以控制能量流. 这项研究通过操纵纳米级的热传递动态,引入了热二极管和热引擎等新的应用.
科学领域:
- 纳米级的传热方式
- 量子热力学就是量子热力学.
- 能源转换技术的使用.
背景情况:
- 近场辐射热传递对于热光伏等能源技术至关重要.
- 以前的研究仅限于静态的,时间独立的系统.
- 动态控制辐射热流仍然是一个重大挑战.
研究的目的:
- 研究时间调制对近场辐射热传递的影响.
- 开发一个理论框架来分析时间依赖的近场辐射热交换.
- 探索时间调节的辐射热传递所能实现的新型应用.
主要方法:
- 为时间调制系统开发严格的波动电动力学形式主义.
- 在时间调制下对辐射传热系数进行理论分析.
- 研究控制热传递动态的对称关系.
主要成果:
- 证明时间调制可以增强,抑制,消除或逆转辐射热流.
- 提出了一个可调节的辐射热二极管,具有无限对比率.
- 推出了一种近场辐射热发动机,能够将热量从冷到热的物体.
结论:
- 时间调制为纳米级辐射热流提供了前所未有的控制.
- 开发的形式主义提供了对时间依赖的辐射现象的基本见解.
- 对于先进的能源技术和热管理应用有很大的潜力.
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