Title :
Numerical study on tungsten selective radiators with various micro/nano structures
Author :
Sai, Hitoshi ; Kanamori, Yoshiaki ; Hane, Kazuhiro ; Yugami, Hiroo ; Yamaguchi, Masafumi
Author_Institution :
Toyota Technol. Inst., Nagoya, Japan
Abstract :
To develop microstructured selective radiators for TPV generation, numerical simulations based on the finite-difference time-domain method were carried out to evaluate spectral properties of various types of surface micro/nano structures: two-dimensional surface-relief gratings with various surface structures such as rectangular holes, cylindrical holes, and micro-pyramids. It was shown that cylindrical holes as well as rectangular holes also realize the cutoff effect with different cutoff wavelengths. On the other hand, W gratings with micro-pyramid array showed high emissivity near unity in the near infrared region due to the anti-reflection effect based on sub-wavelength gratings.
Keywords :
diffraction gratings; emissivity; finite difference time-domain analysis; infrared spectra; nanostructured materials; photovoltaic effects; surface structure; thermophotovoltaic cells; tungsten; TPV generation; W gratings; antireflection effect; cutoff effect; cutoff wavelengths; emissivity; finite-difference time-domain method; micropyramid array; near infrared region; spectral properties; subwavelength gratings; surface micro/nano structures; tungsten selective radiators; two-dimensional surface-relief gratings; Diffraction gratings; Energy conversion; Finite difference methods; Maxwell equations; Microcavities; Numerical simulation; Photovoltaic systems; Surface structures; Time domain analysis; Tungsten;
Conference_Titel :
Photovoltaic Specialists Conference, 2005. Conference Record of the Thirty-first IEEE
Print_ISBN :
0-7803-8707-4
DOI :
10.1109/PVSC.2005.1488244
