Application of the Kragten method in order to evaluate the uncertainty of the heat release rate determination using of the cone calorimeter

Abstract

Assigning uncertainties to measurement results is primordial in a certification framework using fire benches as the cone calorimeter [1] developed by NIST [2]. Indeed, this process allows in the first place to validate the measurement method accuracy and in second place to provide proper results to compare obtained between different labs (reproducibility).However, even if numerous methods enable uncertainties determination, some can become complex when the data of interest is mathematical formulation powered by many measured parameters aimed to use in a model such as the Heat Release Rate (HRR).This article aims to propose an intermediate uncertainty calculation method whose difficulty of application is sized between the GUM method [3] and the Monte Carlo method [4]: the Kragten one [5]. In order to validate the opportunity of using such a method, the three approaches were used to assess the measurement uncertainty on the HRR parameter in the specific case of small scale fire tests using cone calorimeter.The results obtained show that the Kragten method allows to evaluate more easily and faster the HRR uncertainties measured at the Cone Calorimeter than the Monte Carlo method. Furthermore, the Kragten method is more reliable and reduces the risk of miscalculations than the GUM approach.