Uncertainty Quantification for Production Navier-Stokes Solvers

Solution errors are inherent in any Computational Fluid Dynamics (CFD) simulation. Systematic identification, reduction, and control of these various error sources is crucial if the results of CFD simulations are to be trusted for design and performance assessment of air vehicles. While grid refinement studies may verify the spatial accuracy of a solution, these studies are generally laborious and time intensive. Continued development of a standalone Error Transport Equation (ETE) solver is proposed. The proposed program exploits an existing mesh adaptation and error quantification package, CRISP CFDREG, which currently interfaces with meshes and solutions from the NASA unstructured Navier-Stokes solvers FUN3D and USM3D. The Phase I effort will explore the use of ETE methodology with these production Navier-Stokes solvers as well as the popular structured grid code OVERFLOW. Improvements in error prediction for aerodynamic coefficients will be sought. In addition, the proposed program will address uncertainty quantification for turbulence models commonly used in computational aerodynamics applications. The ETE solver provides a promising, viable path for reliable error quantification and solution verification. This tool will provide numerical error bars, quantifiable levels of uncertainty in both local and globally integrated variables, for use in computational aerodynamics and other applications.