Verification of calculations of the potential flow around two-dimensional foils

An example of verification of calculations using methods based on grid-refinement studies and Richardson extrapolation is presented. The study is performed for numerical simulations of the potential flow around two-dimensional lifting foils by one low-order and two higher-order panel methods based on Morino's perturbation potential formulation. Flows with known analytical solutions have been selected to assess the reliability of the uncertainty estimations. The grid-convergence index method is the basis for these estimations. Two options are compared: estimating the uncertainty of the solution on a specific grid and of the solution found by extrapolation to zero grid cell size