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Evaluation of uncertainty in direct measurement for parameterization of pyrolysis models, Part I: Thermal analysis

NCJ Number
Fire Safety Journal Volume: 141 Dated: December 2023 Pages: 104000
Date Published
December 2023

In this article, the authors present the generalized polynomial chaos method for uncertainty propagation, and recommendations to quantify uncertainty in thermal degradation models.


A comprehensive uncertainty analysis is an important part of any engineering calculation because it allows stakeholders to assess the confidence in the conclusions that come from the calculation. Without this necessary step in hypothesis testing and model validation, the true accuracy and confidence of predictions cannot be completely quantified. In this article, the authors present an experimental and analytical approach to determine the kinetics and energetics of pyrolysis which form the foundation for larger scale models of material burning. They present a detailed uncertainty quantification which utilized the generalized polynomial chaos expansion method to propagate uncertainty through the pyrolysis model representation of a thermal analysis experiment. Using this methodology, the authors found the uncertainty in the predictions to be comparable to the uncertainty in the experimental thermal analysis data within calibration conditions. Sensitivity analyses revealed the largest contributor to uncertainty in heat flow rate predictions was the specific heat capacity of all components. Comparison of the uncertainty quantification and sensitivity analyses to well-known results validated the method of uncertainty propagation for more complex scenarios. Publisher Abstract Provided

Date Published: December 1, 2023