Airfoil Analysis with Uncertain Geometry using the Probabilistic Collocation method

Airfoil Analysis with Uncertain Geometry using the Probabilistic Collocation method

Loeven, G.J.A.
Bijl, H.

Aerospace Engineering

Aerodynamics & Wind Energy

2008-04-01

Due to manufacturing tolerances, the airfoil of a wing after production is never exactly the same as the designed airfoil. Also during operation the geometry may change due to aerodynamic loading, icing or wear of the construction. The geometry can, therefore, be treated as uncertain. Uncertainties in the geometry of an airfoil are expected to have a significant influence on quantities like lift and drag. Computational Fluid Dynamics is a tool to investigate the flow around an airfoil, which is characterized by large time consuming computations. Since uncertainty quantification increases the amount of computational work, efficiency is of great importance. To limit the number of uncertain parameters, the geometry is parameterized using a few parameters. The geometric uncertainties are then treated as parametric uncertainties, which are efficiently propagated using the Probabilistic Collocation method. Results are shown for uncertain NACA 4-digit series airfoils, where the maximum camber, maximum camber position and the thickness of the airfoil are assumed to be uncertain. It is shown that geometric uncertainties have significant influence on the drag polar. The uncertainties are propagated through the system separately to see the effect of the parameter on the solution and simultaneously to investigate combined effects.

http://resolver.tudelft.nl/uuid:3ce24d45-5d3d-4868-8419-5fa5625937d8

American Institute of Aeronautics and Astronautics

49th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, Schaumburg, IL, USA, April 7-10, 2008

Institutional Repository

conference paper

(c) 2008 Loeven, G.J.A.
Bijl, H.
AIAA