Uncertainty quantification in rans of lox-ch4 pintle injector

This work presents the numerical characterization, employing an Eulerian-Lagrangian RANS approach, of a pintle-injector liquid rocket engine thrust chamber, fueled with LOX-CH4, and operated at high but still subcritical pressure. Under the thermophysical conditions of interest, the majority of model parameters are challenging to be calibrated, and the Uncertainty Quantification framework represents a natural choice. This research aims at propagating the uncertainty associated with the initial liquid droplets size distribution, employing a Polynomial Chaos Expansion method. The main goal is to assess whether uncertainty on the LOX droplets’ diameters can overshadow the sensitivity to pintle design. The same uncertainty quantification analysis is performed for two pintle injector configurations.