Methodology for estimating measurement uncertainty in the dynamic calibration of industrial temperature sensors

Abstract

This work presents a methodology for estimating the uncertainty of measurements in the calibration of temperature sensors in dynamic regimes for industrial applications. A bare-wire-beaded thermocouple sensor is used as a case study. Typically, this type of sensor responds as a first-order system. A rotating cylindrical tank equipped with an unmasking device was built with a pneumatic triggering especially developed for the purpose of submitting the thermocouple to a temperature step. When rotating, the cylindrical tank generates a channel of infinite length, avoiding sensor interference in the quality of the step generated in the measurement section. A methodology to compute measurement uncertainty in dynamic processes considering the uncertainties of all components of the measurement chain is proposed. Experimental results show that the proposed methodology is adequate to determine measurement uncertainties in the transient phase of the calibration process according to the Guide to the Expression of Uncertainty in Measurements (GUM).