Thomas Olivier Marie Noel

An Uncertainty Quantification Framework Coupled With a 1D Physics-Based Model for the Prediction of NOx Emissions in a RQL Combustion Chamber

From one engine to another with same definition, aerodynamics and combustion may vary depending on several factors such as manufacturing tolerances or thermodynamic conditions. This dispersion has an influence on the physical conditions within the combustor and can impact the emission levels among other things. It is necessary to take into account this variability during all design phases in order to estimate the combustor performances. Uncertainty quantification (UQ) methods provide a set of capabilities for analyzing the impact of this variability. In this article, a non-intrusive UQ methodology is coupled with a 1D physics-based tool which models physical phenomena taking place in the combustor to estimate NOx emissions. A flow analysis is carried out to determine the flow distribution inside the combustor. Then, a simplified kinetic scheme calibrated on engine test results is used to compute the spatial distribution of species mass fractions. Accurate agreement with experiments is observed for several operating points and engines. The impact of the manufacturing tolerances of the diameter of chamber geometrical features on the combustor performances is evaluated. This method provides capabilities to better understand the physics involved improving our knowledge to design efficient combustors.Copyright