Thermal conductivity measurement of insulating materials up to 1000 °C with a needle probe - Archive ouverte HAL
Journal Articles Review of Scientific Instruments Year : 2021

Thermal conductivity measurement of insulating materials up to 1000 °C with a needle probe

Abstract

The hot wire method is one of the few methods that can be applied to measure the thermal conductivity of materials at 1000 °C and above. However, in the case of granular or electrically conductive materials, the heating wire and thermocouple must be insulated from the material by placing them in a sheath (or a needle). In this case, it is shown that the method of using the slope of the curve T = f[ln(t)] could lead to estimation errors of up to 30% for some materials. A complete quadrupolar model of the system needle/material is developed, and a sensitivity analysis of the probe temperature to the different parameters allowed for the selection of a reduced model, enabling a precise estimation of the thermal conductivity. Measurements carried out between 600 and 1000 °C on a material of known thermal conductivity led to deviations of less than 3%. The method is finally applied up to 1000 °C to two granular materials and to compacted molding sand with quite a good fitting between the experimental and modeled curves.
No file

Dates and versions

hal-03261124 , version 1 (15-06-2021)

Identifiers

Cite

Yves Jannot, Dorsaf Khalifa, Léa Penazzi, Alain Degiovanni. Thermal conductivity measurement of insulating materials up to 1000 °C with a needle probe. Review of Scientific Instruments, 2021, 92 (6), pp.064903. ⟨10.1063/5.0050000⟩. ⟨hal-03261124⟩
64 View
0 Download

Altmetric

Share

More