METHOD OF MEASURING THERMAL DIFFUSIVITY OF HEAT-INSULATING MATERIALS BY REGULAR THIRD KIND MODE TECHNIQUE

摘要

FIELD: physics.;SUBSTANCE: two temperature sensors, made in form of thermocouples or resistance thermometers, are placed in a prepared flat sample of the analysed material in sections with coordinates x=x₁ and x=x₂. The sample, whose top is heat insulated, is placed on the surface of a Peltier element which is a source of harmonic temperature oscillations. By varying the period τ₀ of the harmonic oscillations of the Peltier element, an operating mode of the measuring devices is selected, at which the value differs by not more than a small value ε=0.002…0.009 from a given value ψ_v from the range (0.14…0.18), which enables to calculate the unknown value of thermal diffusivity with the least error.;EFFECT: high accuracy of measuring thermal diffusivity of heat-insulating materials.;2 dwg