Adaptive viscous-inviscid interaction method for analysis of airfoils in ground effect

The behavior of an airfoil in ground proximity is significantly different from out of ground. Therefore, understanding the effect of proximity to ground can help determine its aerodynamic characteristics, which are important design parameters. In this paper, an accurate viscous-inviscid interacting method is investigated as an alternative method to computing heavy Navier-Stokes solution for utilizing in the surface effect zone. The inviscid part is modeled by a 2D panel method, and the viscous part is modeled by solving the integral form of the laminar and turbulent boundary layer equations. Validation of the incompressible 2D version of the written code (so-called WIGPMBL) is carried out against experimental and other numerical codes for different airfoil geometries at various Reynolds numbers. Various aspects of aerodynamic characteristics such as pressure distribution, lift and drag coefficient, transition and separation points of symmetric and asymmetric airfoils have been validated. Consequently, the assessments have verified that the present method has good accuracy for predicting the effect of surface proximity.