Uncertainty Quantification of k-ω Turbulence Model for Hypersonic Flow

The formulation of turbulence models contains a considerable source of uncertainty. The goal of this work is to investigate the uncertainty and sensitivity of k-ω model due to uncertainty in the values of closure coefficients. Specifically, uncertainty analysis is performed for hypersonic flow over an all-body aircraft. In the current study, firstly a stochastic expansion based on point collocation Non-Intrusive Polynomial Chaos (NIPC) expansion is utilized to identify the uncertainties. Then Sobol indices are used to rank the relative contribution of each closure coefficient. The sensitivity analysis showed that σ contributes most in hypersonic flow both in heat flux and pressure in most areas, while near the expansion shock β* becomes the top contributor for uncertainty of pressure.