Experimental investigation of the thermal conductivity of construction materials

Abstract

In this study, an instrument for examination of the heat conductivity of – mainly – construction materials is presented. The heat flow within the material can be examined both in the function of time and spatial position with this instrument. For this purpose, a small heat-insulated chamber with digital thermostat was constructed in which the temperature of the air can be set. The quasi constant temperature allows that the heat-conduction of a specimen placed in a part of the chamber – designed for this purpose – can be determined. The heat conductivity of the chamber is much lower than that of the specimen thus almost all of the heat flow goes through the specimen. Thermocouples were placed in several positions and depth of the specimen. The time series of the signals of the thermocouples were acquired with computer. As a result of the data processing of the time series of temperature values the thermal characteristics of the specimen can be determined.