Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 05, 2021 - September 08, 2021
Thermal switching and thermal diodes have been actively studied from the viewpoint of effective energy utilization and temperature control. Compared to heat conduction and convective heat transfer, the radiation heat transport is more easily accompanied by temperature gradients which can produce strong thermal non-equilibrium. The amount of heat transport is proportional to the fourth power of temperature. In this study, we developed a wavelength-selective thermal switching device consisting of a blackbody heater and a wavelength-selective emitter. For wavelength selective emitter, we fabricated silver-alumina cermet films by the MOD method. The fabricated cermet films showed a normal spectral absorptance of about 0.8 at short wavelengths and 0.1 at long wavelengths. Results show found that the device is adiabatic when the heater temperature is below the operating temperature, but the heat flux increases exponentially when the heater temperature is above the operating temperature. It was also found that the operating temperature can be controlled by controlling the cutoff wavelength.
