RANS-Based Aerodynamic Shape Optimization of a Wing Considering Propeller-Wing Interaction

The recent growth of interest in hybrid-electric and fully electric aircraft has led to a renewed focus on the design and optimization of propeller aircraft. Considering propeller-wing interaction provides the opportunity to design aircraft that take advantage of aerodynamic benefits through propulsion integration. In this paper, the cruise drag of a wing with an inboard-mounted tractor propeller is minimized using aerodynamic shape optimization. Reynolds-averaged Navier-Stokes computational fluid dynamics with an actuator-disk approach is used for the simulations, and a gradient-based algorithm is used for the optimization. Changing the rotation direction of the propeller and optimizing the twist and airfoil shapes of the wing impact the aerodynamic performance significantly. However, optimizing the wing while considering the propeller slipstream provides little additional benefit compared to optimizing it without considering the propeller slipstream (the difference is less than one drag count). The wings optimized without considering the propeller slipstream are naturally able to recover swirl almost as effectively as the wings optimized while considering the propeller slipstream, and the propeller-induced velocities for the cruise condition are not high enough to lead to significant airfoil-shape design changes.