Multi-Fidelity High-Lift Aerodynamic Optimization of Single-Element Airfoils

We describe a computationally efficient simulation-driven design methodology for single-element airfoils at high-lift conditions. Direct optimization of an accurate but computationally expensive high-fidelity simulation model based on Reynolds-Averaged Navier-Stokes equations is replaced by iterative updating and re-optimization of a cheap surrogate. The surrogate model exploits a low-fidelity model (a polynomial approximation of the high-fidelity model data) and appropriate correction that aim at aligning its corresponding airfoil surface pressure distribution and skin friction distribution with that of the high-fidelity model using a shape-preserving response prediction technique. The test cases include lift coefficient maximization of single-element airfoils at high-lift conditions, subject to a constraint on the drag coefficient. Over 83% reduction in number of high-fidelity model simulations is demonstrated when compared to high-fidelity model optimization using a pattern-search algorithm.