塗料式輻射冷卻材料

Paint-Format Radiative Cooling Material

李文豪(Wen-Hao Li)

指導教授 ： 李佳翰

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202101739

摘要

我們以輻射冷卻為主要研究方向，並以此基礎製作散熱材料。基於輻射冷卻製作之散熱材料的原理為提升材料的紅外線發射率，使紅外線輻射出物體外，以提升物體的散熱效果。黑體輻射為輻射冷卻的理論基礎。黑體輻射在室溫300K的溫度下，物體會輻射出波長落在5 μm ~ 25 μm的紅外線，當中以8 μm ~ 13 μm的範圍佔據了大部分的輻射功率。因此製作出對此波長範圍有高發射率的材料即為我們的目標。我們以光學模擬軟體分析材料在不同條件下對於紅外線光譜中的表現，並尋找較高紅外線發射率的情況。冷卻材料製作部分料，我們以二氧化矽微米球以及空心微米玻璃球 結合透明塗料製作輻射冷卻材料。實驗部分，我們架設輻射冷卻之實驗系統並將此系統結合戶外實驗。由於輻射冷卻的實驗中不只會牽扯到光學，外在環境的影響也會使冷卻效果降低。由於太陽光為造成地球升溫之主要熱源，同時陽光也是影響實驗散熱效果之主要因素，因此將實驗系統架設至戶外為模擬在陽光下加熱之情況。戶外實驗的干擾因素眾多，除了太陽光加熱以外，也會有空氣之熱平衡、實驗架設環境之影響，即使在戶外，實驗在外在環境干擾甚多的情況下，實驗結果顯示輻射冷卻材料也能將物體冷卻。

關鍵字

輻射冷卻 ； 散熱 ； 冷卻塗料 ； 玻璃微米球 ； 高紅外線吸收率

並列摘要

Heat dissipation is a fundamental problem in various fields. In this research, the heat dissipation materials with radiative cooling are studied. Based on radiative cooling, the material with high infrared emittance is desired to improve the cooling efficiency. According to the black body radiation theory, the object radiates infrared at room temperature (300K). The wavelength of the light emitted by the object is from 5 μm to 25 μm. The light with the wavelength between 8 μm and 13 μm takes most of the irradiance power at room temperature. Therefore, making high infrared emitted material is the key to success of radiative cooling materials. The silicon dioxide microspheres are used and combined with common polymer. The performance of the cooling materials are simulated by with the optical simulation software and the good design of the radiative cooling material can be found. In the experimental part, a radiative cooling experimental system is set up in consideration of the outdoor experiments. Not only the radiation but also thermal heat from the environment affect the cooling performance of radiative cooling material. Sunlight is the main heat source for the earth, which causes the earth warms up. In the experiment, sunlight is the main factor that affects the cooling performance. Therefore, the experiment is set up on the rooftop and the cooling performance of cooling material is tested under the sun. There are many interfering factors in outdoor experiments. In addition to solar energy, the thermal equilibrium between air and sample and the experimental environment can affect the cooling performance of cooling material. The experiment results show that the radiating cooling material can cool down the outdoor object.

並列關鍵字

daytime radiative cooling ； heat dissipation ； cooling paint ； glass microsphere ； infrared absorption

參考文獻

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