A Monte Carlo approach to evaluate the local measurement uncertainty in transient heat transfer experiments using liquid crystal thermography

Abstract

This work presents an improved estimation of the local measurement uncertainty of transient heat transfer experiments using Thermochromic Liquid Crystals (TLC). Additional signal analysis steps and a Monte Carlo (MC) approach are added to the evaluation routine. As a result, the local uncertainty in the indication time of the maximum green intensity is determined. All other input quantities for the heat transfer coefficient calculation are provided with their characteristic distribution function introducing additional uncertainties. As a final result, lower and upper boundaries for a confidence interval with a user defined confidence level for the heat transfer coefficient are calculated locally for single pixels. The new method is applied to own measurement data from a transient TLC experiment. The local measurement uncertainty is compared to the traditional approach based on error propagation. Hence, the advantages of taking the non-linearity and the local uncertainty in the peak detection into consideration are shown.