Near-wall grid adaptation for turbulent flows

This paper considers grid-adaptation techniques for the boundary-layer region of hybrid meshes, where the mesh is of regular structure consisting of prismatic respectively hexahedral elements. The method helps to improve convergence, accuracy and reliability of aerodynamic simulations for the two possible types of wall-boundary conditions for viscous flows, i.e., integrating the flow equations down to the wall (no-slip) or using wall-functions. The underlying algorithms and their parallelisation are described and the method is applied to 3D aerodynamic configurations. Moreover, accuracy and performance gain through the use of wall-functions with grid-adaptation are discussed for transonic airfoil flows.