Numerical Studies of the NASA Tiltwing Multi-Rotor Conceptual Aircraft

NASA’s Tiltwing Urban Air Mobility (UAM) concept represents a model case to study the aerodynamic performance for an electric vertical takeoff and landing (eVTOL) aircraft, that combines the benefits of vertical lift with the aerodynamic efficiency of fixed-wing cruise. This paper presents ongoing computational work focused on evaluating the aerodynamic performance of the Tiltwing configuration in both hover and cruise conditions. Computational Fluids Dynamics (CFD) computations are conducted using the commercial finite volume-based CFD solver ANSYS Fluent, comparing results using both the steady state Virtual Blade Model (VBM) and the unsteady Sliding Mesh Method (SMM). In the hover regime, the study aims to investigate rotor–rotor and rotor–airframe interactions that influence induced power and stability. In cruise, attention is directed toward assessing aerodynamic efficiency, propeller thrust performance, and the impact of the tilt wing configuration. The two modeling approaches for each configuration will support a comparative analysis between computational accuracy and cost-effectiveness, with the goal of informing early-stage design decisions. Preliminary results indicate that the VBM model compares well with SMM results for cruise while the hover configurations exhibit greater differences.