Application of a Pragmatic Interval-Based "Real Space" Approach to Fire-Model Validation Involving Aleatory and Epistemic Uncertainty.

This paper applies a pragmatic interval-based approach to validation of a fire dynamics model involving computational fluid dynamics, combustion, participating-media radiation, and heat transfer. Significant aleatory and epistemic sources of uncertainty exist in the experiments and simulations. The validation comparison of experimental and simulation results, and corresponding criteria and procedures for model affirmation or refutation, take place in “real space” as opposed to “difference space” where subtractive differences between experiments and simulations are assessed. The versatile model validation framework handles difficulties associated with representing and aggregating aleatory and epistemic uncertainties from multiple correlated and uncorrelated source types, including: experimental variability from multiple repeat experiments uncertainty of experimental inputs experimental output measurement uncertainties uncertainties that arise in data processing and inference from raw simulation and experiment outputs parameter and model-form uncertainties intrinsic to the model numerical solution uncertainty from model discretization effects.