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08:44
Fabrication and Testing of Photonic Thermometers
Published on: October 24, 2018
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Photonic thermal management of coloured objects
Wei Li1, Yu Shi1, Zhen Chen1,2
1Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, CA, 94305, USA.
Nature Communications
|October 14, 2018
Summary
Controlling radiative thermal load is crucial for colored objects. Photonic structures offer a wide tunable range for heating or cooling, demonstrating significant temperature differences even for the same color.
Area of Science:
- Materials Science
- Thermodynamics
- Optics
Background:
- Object color is typically chosen for aesthetics or function.
- Controlling radiative thermal load is essential for heating and cooling applications.
- Existing color choices do not inherently manage thermal load effectively.
Purpose of the Study:
- To calculate the tunable range of radiative thermal load for all colors.
- To demonstrate the potential of photonic structures for thermal management.
- To investigate the impact of color on an object's temperature under sunlight.
Main Methods:
- Comprehensive calculation of tunable radiative thermal load.
- Experimental demonstration using photonic structures.
- Comparison with commercial paints under solar irradiation.
Main Results:
- Tunable range of radiative thermal load exceeds 680 W/m² for all colors, reaching up to 866 W/m².
- Photonic structures with the same pink color exhibited temperature differences of 47.6°C under sunlight.
- Structures were over 20°C different from commercial paints and 10°C hotter than black paint.
Conclusions:
- Photonic thermal management offers significant potential for colored objects.
- Color and thermal properties can be independently controlled using photonic structures.
- These findings enable advanced thermal management strategies for diverse applications.
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