Uncertainty Quantification and Sensitivity Analysis of Turbulence Model Coefficients for the Common Research Model

Project Description

There is currently a high demand for turbulence modeling uncertainty quantification (UQ) and sensitivity analysis. In a coordinated study between NASA, Boeing, and others, Slotnick et al. propose a vision for the capabilities of CFD technology in the year 2030, as well as a number of suggestions for how to reach that point [3]. One of the basic capabilities the authors envision by 2030 is the management of errors and uncertainties arising from “all possible sources.” These sources include physical modeling errors and uncertainties due to turbulence, as well as epistemic uncertainties due to lack of knowledge in the parameters of particular fluid flow problems. Accurate prediction of turbulent flow and the currently limited use of UQ are both listed as current CFD technology gaps and impediments. The former is described as “perhaps the single, most critical area in CFD simulation capability.”The proposed research seeks to improve knowledge of turbulent flows by performing UQ on the Common Research Model (CRM). The CRM was developed for the purpose of validating CFD codes. It consists of a contemporary supercritical transonic wing and a fuselage that is representative of a wide-body commercial transport aircraft [4]. The CRM has been a primary focus of the CFD Drag Prediction Workshop Series [5], which is a community effort to improve CFD technology. The proposed research will quantify the amount of uncertainty in the CRM case, and will provide guidelines for how that uncertainty can be reduced. This will allow Boeing and others to improve the accuracy of CFD.For Boeing specifically, more accurate CFD will significantly lower business costs. As CFD accuracy improves, wind tunnel testing can be replaced. This shortens product development time and reduces the number of costly wind tunnel experiments. More accurate CFD could also lead to certification by analysis, reducing the need for expensive flight tests of new aircraft.