Sub-ambient daytime radiative cooling (SA-DRC) has been demonstrated by various advanced emitters in recent studies, which have attracted considerable attention from fundamental sciences and potential applications. Apart from emitter's unique radiative properties, the cooling loss of the emitter affects the performance of SA-DRC in actual applications. Although the emitter is fixed in an enclosure space to decrease the effect of ambient wind on the performance of cooling, the cooling loss of the emitter still exists, and an effective heat transfer coefficient between the emitter and ambient air has directly been widely used to predict the magnitude of the cooling loss power. However, this mathematical description is limited, which will lead to a controversial prediction in some cases. In this study, the cooling loss of the emitter was investigated based on a local environment. The simulation was conducted on the basis of four advanced emitters that were reported in recent studies, and the results show that the cooling loss of the emitter increases with the increasing interface temperature of the enclosure space that surrounds the emitter, which weakens the cooling effect of the emitter. A case study shows that the temperature reduction of an infrared-spectral-selective emitter could be degraded from −3.2 °C to 0.1 °C when the interface temperature increases from ambient temperature to 6 °C higher than ambient temperature, which implies that the cooling effect has been entirely destroyed.Sub-ambient daytime radiative cooling (SA-DRC) has been demonstrated by various advanced emitters in recent studies, which have attracted considerable attention from fundamental sciences and potential applications. Apart from emitter's unique radiative properties, the cooling loss of the emitter affects the performance of SA-DRC in actual applications. Although the emitter is fixed in an enclosure space to decrease the effect of ambient wind on the performance of cooling, the cooling loss of the emitter still exists, and an effective heat transfer coefficient between the emitter and ambient air has directly been widely used to predict the magnitude of the cooling loss power. However, this mathematical description is limited, which will lead to a controversial prediction in some cases. In this study, the cooling loss of the emitter was investigated based on a local environment. The simulation was conducted on the basis of four advanced emitters that were reported in recent studies, and the results show tha...

中文翻译：

---

考虑辐射冷却发射器的冷却损失过程

在最近的研究中，各种先进的发射器已经证明了亚环境日间辐射冷却 (SA-DRC)，这引起了基础科学和潜在应用的广泛关注。除了发射器独特的辐射特性外，发射器的冷却损失也会影响 SA-DRC 在实际应用中的性能。虽然发射器固定在封闭空间内以减少环境风对冷却性能的影响，但发射器的冷却损失仍然存在，并且发射器与环境空气之间的有效传热系数已直接被广泛用于预测冷却损失功率的大小。然而，这种数学描述是有限的，这在某些情况下会导致有争议的预测。在这项研究中，根据当地环境研究了发射器的冷却损失。仿真是在近期研究报道的四种先进发射器的基础上进行的，结果表明发射器的冷却损失随着围绕发射器的外壳空间界面温度的升高而增加，从而削弱了发射器的冷却效果。发射器。一个案例研究表明，当界面温度从环境温度增加到比环境温度高 6°C 时，红外光谱选择性发射器的温度降低可能从 -3.2°C 降低到 0.1°C，这意味着冷却效果已完全被破坏。 在最近的研究中，各种先进的发射器已经证明了亚环境日间辐射冷却 (SA-DRC)，引起了基础科学和潜在应用的广泛关注。除了发射器独特的辐射特性外，发射器的冷却损失也会影响 SA-DRC 在实际应用中的性能。虽然发射器固定在封闭空间内以减少环境风对冷却性能的影响，但发射器的冷却损失仍然存在，并且发射器与环境空气之间的有效传热系数已直接被广泛用于预测冷却损失功率的大小。然而，这种数学描述是有限的，这在某些情况下会导致有争议的预测。在本研究中，基于局部环境研究了发射器的冷却损失。