Basic Study on Effects of Water Content on Printing Paper on Equivalent Thermal Conductivity

Currently, there are few studies on the influence of microscale thermal radiation on the equivalent thermal conductivity of microscale porous metal. Therefore, this paper calculated the equivalent thermal conductivity of high-porosity periodic cubic silver frame structures with cell size from 100 nm to 100 µm by using the microscale radiation method. Then, the media radiation characteristics, absorptivity, reflectivity and transmissivity were discussed to explain the phenomenon of the radiative thermal conductivity changes. Furthermore, combined with spectral radiation properties at the different cross-sections and wavelength, the radiative transmission mechanism inside high-porosity periodic cubic frame silver structures was obtained. The results showed that the smaller the cell size, the greater radiative contribution in total equivalent thermal conductivity. Periodic cubic silver frames fluctuate more in the visible band and have better thermal radiation modulation properties in the near infrared band, which is formed by the Surface Plasmon Polariton and Magnetic Polaritons resonance jointly. This work provides design guidance for the application of this kind of periodic microporous metal in the field of thermal utilization and management.

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Validation of a gas chromatography/thermal conductivity detection method for the determination of the water content of oxygenated solvents

Journal of Chromatography A ◽

10.1016/j.chroma.2007.12.044 ◽

2008 ◽

Vol 1182 (1) ◽

pp. 113-118 ◽

Cited By ~ 17

Author(s):

W.K. O’Keefe ◽

F.T.T. Ng ◽

G.L. Rempel

Keyword(s):

Thermal Conductivity ◽

Gas Chromatography ◽

Water Content ◽

Detection Method ◽

Conductivity Detection

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Effective Thermal Conductivity of Open Cell Polyurethane Foam Based on the Fractal Theory

Advances in Materials Science and Engineering ◽

10.1155/2013/125267 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Kan Ankang ◽

Han Houde

Keyword(s):

Thermal Conductivity ◽

Fractal Dimension ◽

Effective Thermal Conductivity ◽

Polyurethane Foam ◽

Solid Phase ◽

Fractal Theory ◽

Heat Radiation ◽

Total Thermal Conductivity ◽

Equivalent Thermal Conductivity ◽

Open Cell

Based on the fractal theory, the geometric structure inside an open cell polyurethane foam, which is widely used as adiabatic material, is illustrated. A simplified cell fractal model is created. In the model, the method of calculating the equivalent thermal conductivity of the porous foam is described and the fractal dimension is calculated. The mathematical formulas for the fractal equivalent thermal conductivity combined with gas and solid phase, for heat radiation equivalent thermal conductivity and for the total thermal conductivity, are deduced. However, the total effective heat flux is the summation of the heat conduction by the solid phase and the gas in pores, the radiation, and the convection between gas and solid phase. Fractal mathematical equation of effective thermal conductivity is derived with fractal dimension and vacancy porosity in the cell body. The calculated results have good agreement with the experimental data, and the difference is less than 5%. The main influencing factors are summarized. The research work is useful for the enhancement of adiabatic performance of foam materials and development of new materials.

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