Effect of Turbulence Model Uncertainty on Scramjet Isolator Flowfield Analysis


The goal of this work was to quantify the uncertainty in the solution of a scramjet isolator flowfield due to the uncertainty in the closure coefficients of commonly used turbulence models in Reynolds-averaged Navier-Stokes simulations. The Menter baseline, Menter shear stress transport, Spalart-Allmaras, and Wilcox-2006 k - ω turbulence models were examined; and simulations were carried out using the VULCAN flow solver. Nonintrusive polynomial chaos theory was used for efficient uncertainty propagation, and Sobol indices were employedto establish relative sensitivities of the flow solution to closure coefficients. The results obtained were compared to experimental dataaswell as toprevious work focusingon relevant flow problems. Sets of closure coefficients that contribute most to solution uncertainty for each turbulence model were identified, which warrant further investigation because more knowledge about the effects of these coefficients is expected to reduce the uncertainty in the numerical design of scramjet isolators.


Mechanical and Aerospace Engineering

Research Center/Lab(s)

Center for High Performance Computing Research

Keywords and Phrases

Chaos theory; Flow fields; Navier Stokes equations; Polynomials; Ramjet engines; Shear flow; Shear stress; Turbulence models, K-Omega turbulence model; Model uncertainties; Numerical design; Polynomial chaos theory; Relative sensitivity; Reynolds-averaged navier-stokes simulations; Shear-stress transport; Uncertainty propagation, Uncertainty analysis

International Standard Serial Number (ISSN)

0748-4658; 1533-3876

Document Type

Article - Journal

Document Version


File Type





© 2020 The Authors, All rights reserved.

Publication Date

01 Jan 2020