The influence of soil moisture in thermal infrared emissivity is a known fact, but poorly studied in the past. An experiment for quantifying the dependence of emissivity on soil moisture has been designed. Six samples of superficial horizons of different Mediterranean soil types have been selected. Their emissivity has been measured at different soil water contents, using the twolid variant of ...

This study explores the estimation of land surface temperature (LST) for the globe from Landsat 5, 7 and 8 thermal infrared sensors, using different surface emissivity sources. A single channel algorithm is used for consistency among the estimated LST products, whereas the option of using emissivity from different sources provides flexibility for the algorithm’s implementation to any area of in...

A three-dimensional numerical study was made to investigate effects of fin angle, fin surface emissivity, and tube wall temperature on heat transfer enhancement for a longitudinal externally-finned tube placed vertically in a small chamber. The numerical model was first validated through comparison with experimental measurements and the appropriateness of general boundary conditions was examine...

Selective thermal emission in a useful range of energies from a material operating at high temperatures is required for effective solar thermophotovoltaic energy conversion. Three-dimensional metallic photonic crystals can exhibit spectral emissivity that is modified compared with the emissivity of unstructured metals, resulting in an emission spectrum useful for solar thermophotovoltaics. Howe...

Fabrication of devices and circuits on silicon wafers creates patterns in optical properties, particularly the thermal emissivity and absorptivity, that lead to temperature nonuniformity during rapid thermal processing (RTP) by infrared heating methods. The work reported in this paper compares the effect of emissivity test patterns on wafers heated by two RTP methods: (1) a steadystate furnace ...

It is well known that the efficiency of thermodynamic solar plants increases with the working temperature. At present the main limit in temperature upscaling is the absorber capability to withstand high temperatures. The ideal solar absorber works at high temperatures, has a low thermal emissivity and a high absorptivity in the solar spectral range . The paper reports on the high temperature em...

A practical physics-based regression method was developed and evaluated for nearly real time estimate of land surface emissivity spectra in 8-14 μm from hyperspectral thermal infrared data. Two spectral emissivity libraries and one atmospheric profile database fully covering all the possible situations for clear sky conditions were elaborately selected to simulate the radiances at the top of th...

The present paper studies a structure consisting of a periodic metallic grating, coated on a dielectric spacer atop an opaque metal substrate, using coherent thermal emission source in the infrared region. It has been theoretically demonstrated that by exciting surface magnetic polaritons between metallic gratings and an opaque metallic film, separated by a dielectric spacer, large emissivity p...

Spectral control of the emissivity of surfaces is essential in applications such as solar thermal energy and thermophotovoltaic energy conversion in order to achieve the highest conversion efficiencies possible. We investigated surfaces consisting of periodic, nanoscale V-grooves coated with aperiodic metal-dielectric stacks. This approach combines impedance matching using tapered metallic feat...