Cubic spline interpolation & profile geometry effects on the potential flow solutions
Salah JS El-Ibrahim
Many Computational Fluid Dynamics (CFD) codes used for the solution of the potential flow around two dimensional aerofoil sections normally use a cubic spline to represent the coordinate data of the given profile in order to provide smooth functions for the conformal mapping procedure (to map the profile into a circle and reflect the data onto a computational grid, with the need for the splined data to match the grid’s resolution points on the profile’s surface). Depending on the supplied (input data) of the profile, the cubic spline may exhibit oscillatory behaviour that may reflect onto the solution of the flow parameters and make it unreliable. The present work attempts to test this behaviour with the Viscous Garabedian & Korn (VGK) code and to assess the code’s performance with profiles having non-smooth geometries representing indentations (damages) to wings simulating accidental real-life damages.