Consistency, Stability and Convergence of the Viscous Garabedian and Korn (VGK) Method

The Viscous Garabedian and Korn (VGK) is a computational fluid dynamics (CFD) code, used for the prediction of viscous flows around two dimensional aerofoil sections (mapped onto a circular grid) in a subsonic free stream. The code is written in “Fortran 77” and solves the full potential flow equations using a finite difference algorithm. The code has been recently published commercially with a data preparation routine to facilitate its use [1]. The present work investigates the code’s consistency, stability and convergence in the hope that it will shed light on the code’s performance and limitations under various flow conditions and code’s numerical parameters.