Uncertainty Analysis of the Mean Radiant Temperature Measurement based on Globe Temperature Probes

Abstract

Nowadays, due to the importance that aspects related to energy efficiency and indoor environmental quality have assumed, the need to carry out audits in which the thermal comfort indices are assessed has grown substantially. A particularly relevant issue is the quality of the experimental results, which is directly connected to the uncertainty of the indices values. The evaluation can be based on the PMV-PPD indices or on the Adaptive Model method, and in both an inescapable environmental variable is the mean radiant temperature. It can be obtained from different methods, being the most used the one based upon the simultaneous measurement of the globe temperature, the air temperature and the air speed. In the work reported in this paper, the impact of the aforementioned environmental variables and their uncertainties on the combined expanded uncertainty of mean radiant temperature has been studied, for two diameters of the globe temperature probe and for two metrological quality conditions of the used probes. The calculations were performed using the Monte Carlo method.