An inverse problem for estimation of the drag and lift coefficients of wing sections

An inverse analysis was conducted to estimate the drag and lift coefficients in incompressible turbulent flow over symmetric and asymmetric wing sections based on measurements of wake velocities. Inverse analysis is based on momentum and mass conservation laws over a control volume. The drag and lift coefficients can be determined as unknown parameters by the Levenberg-Marquardt algorithm. Several simulations were conducted by Open-FOAM software to appraise the inverse algorithm that was developed. Three different kinds of wing sections, namely NACA0009, NACA0018, and NACA23012, were selected for simulation and estimation of the forces. Each of sections was simulated at three different angles of attack. The estimated drag and lift coefficients were validated using values reported in the literature. It was shown that the proposed inverse method can estimate the drag and lift coefficients with very good accuracy. The results obtained were found to be independent of the location of the velocity measurements.