An extended hot plate method for measurement of thermal conductivity variation with temperature of building materials

摘要

A new exploitation of the Hot Plate in Steady state HPS on the determination of thermal conductivity variation with temperature is presented. The mean temperature changement with temperature of the tested sample is ensured with varying the value of the voltage applied to the hot plate resistance, which enables to measure the thermal conductivity in different temperatures. Calculated thermal conductivity values obtained using a gypsum plaster sample, which specific heat capacity variation with temperature is accurately measured, validate the technic. Results show that the mean calculated thermal conductivity of the studied gypsum plaster is 0,143 W/m.k while the measured one is 0,148 W/m.k with a mean deviation of 3,81%. Moreover, the two trend lines of measured values and calculated ones have the same slope with a small intercept difference of 0,004.