The Combined Relative Uncertainty of Measurement Results by Prototype Semi-Automated Calorimetric Chamber

Abstract

The paper presents an evaluation of the combined relative uncertainty of the result of direct step temperature measurements aimed at evaluation of the indirect measurements of the specific thermal capacity of the heat insulating concrete by means of a pair of resistive cable thermometers fitted with Pt100 temperature sensors and integrated into a computer-controlled calorimetric chamber. In particular, it is a proposal of evaluation of the overall relative uncertainty of the measurement of partial temperatures measured in equidistant time steps, in a relatively wider time interval. In practice, the uncertainty of the result of step temperature measurements is most often declared only by the instrument uncertainty specified by the manufacturer. The exact evaluation of the result of the measurements of thermal and temperature material parameters measured by the calorimetric comparison method is required by the fact that the investigated samples are made of newly designed non-tabulated building materials and that the measurements are made by a prototype device.

Keywords

• Combined relative uncertainty
• step temperature measurement
• specific thermal capacity
• semi-automated calorimetric chamber