A gPC-based approach to uncertain transonic aerodynamics
Date
2010Source Title
Computer Methods in Applied Mechanics and Engineering
Print ISSN
0045-7825
Volume
199
Issue
17-20
Pages
1091 - 1099
Language
English
Type
ArticleItem Usage Stats
188
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Abstract
The present paper focus on the stochastic response of a two-dimensional transonic airfoil to parametric uncertainties. Both the freestream Mach number and the angle of attack are considered as random parameters and the generalized Polynomial Chaos (gPC) theory is coupled with standard deterministic numerical simulations through a spectral collocation projection methodology. The results allow for a better understanding of the flow sensitivity to such uncertainties and underline the coupling process between the stochastic parameters. Two kinds of non-linearities are critical with respect to the skin-friction uncertainties: on one hand, the leeward shock movement characteristic of the supercritical profile and on the other hand, the boundary-layer separation on the aft part of the airfoil downstream the shock. The sensitivity analysis, thanks to the Sobol' decomposition, shows that a strong non-linear coupling exists between the uncertain parameters. Comparisons with the one-dimensional cases demonstrate that the multi-dimensional parametric study is required to get the correct shape and magnitude of the standard deviation distributions of the flow quantities such as pressure and skin-friction. © 2009 Elsevier B.V.
Keywords
Polynomial chaosStochastic collocation
Transonic airfoil aerodynamics
Uncertain quantification
Boundary-layer separation
Coupling process
Flow quantities
Flow sensitivity
Freestream mach number
Generalized polynomial chaos (gPC)
Movement characteristics
Nonlinear coupling
Nonlinearities
Numerical simulation
Parametric study
Parametric uncertainties
Polynomial chaos
Random parameters
Spectral collocation
Standard deviation
Stochastic collocation
Stochastic parameters
Stochastic response
Super-critical
Transonic airfoils
Two-dimensional transonic airfoil
Uncertain parameters
Uncertain quantification
Airfoils
Chaos theory
Friction
Mach number
Polynomials
Sensitivity analysis
Stochastic systems
Uncertainty analysis
Transonic aerodynamics
Permalink
http://hdl.handle.net/11693/22413Published Version (Please cite this version)
http://dx.doi.org/10.1016/j.cma.2009.11.021Collections
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