Method for measuring hemispherical total emissivity and heat conductivity of large temperature difference sample

Abstract

The invention discloses a method for measuring hemispherical total emissivity and heat conductivity of a large temperature difference sample. The method comprises the following steps of: heating a belt-shaped conductor sample by electrifying under a vacuum environment, and arranging a plurality of thermocouple measuring points along the axial direction of the sample; forming a sample analysis region, and measuring to get the current value and the voltage value of the analysis region; dividing the sample into a plurality of infinitesimal control bodies along the axial direction, building a steady-state energy balance equation of the infinitesimal control bodies, and respectively expressing the hemispherical total emissivity and the heat conductivity as mathematical functions about temperature; performing multiple groups of steady-state measurement experiments under different steady-state temperature conditions to form a plurality of steady-state energy balance equations; calculating the temperature distribution of each infinitesimal control body under different steady states, and the total emissivity and the heat conductivity of each infinitesimal control body under different steady-state temperature conditions. According to the method disclosed by the invention, the problem that the hemispherical total emissivity of the large temperature difference conductor material sample of which the heat conductivity is unknown cannot be measured in the prior art.

Description

technical field [0001] The invention relates to the field of measuring the hemispherical total emissivity of conductive materials, in particular to a method for measuring the hemispherical total emissivity and thermal conductivity of samples with large temperature differences. Background technique [0002] Hemispherical total emissivity is one of the important thermophysical parameters of materials, which characterizes the surface thermal radiation ability of materials, and is an important basic physical property data for the study of radiation measurement, radiation heat transfer and thermal efficiency analysis. With the wide application of new materials in high-tech fields such as energy power and aerospace, more urgent needs have been put forward for the measurement of hemispherical total emissivity. Compared with other thermal physical parameters, the hemispherical total emissivity measurement method The technical research is still insufficient, and the hemispherical ful...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a method for measuring the hemispherical total emissivity and thermal conductivity of samples with a large temperature difference, so as to overcome the problem that the existing technology cannot measure the hemispherical total emissivity of large temperature difference conductor material samples with unknown thermal conductivity

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