Assessment of computational fluid dynamics simulation approach for the aerodynamic performance of small unmanned aerial vehicle propeller

Abstract This study explores the complexities of UAV propeller aerodynamics by examining the influence of various parameters, including mesh resolutions, timestep sizes, iterations per timestep, and different Reynolds-Averaged Navier–Stokes (RANS) turbulence models, using Delayed Detached Eddy Simulation (DDES). Through extensive computational fluid dynamics (CFD) simulations, the aerodynamic performance of the propeller is analyzed under different conditions. Mesh resolutions from coarse to fine are evaluated, with Grid Convergence Index (GCI) and Richardson Extrapolation applied to ensure mesh-independent results. Timestep sizes ranging from 0.5° to 10° are also analyzed, revealing a trade-off between accuracy and computational efficiency. Furthermore, the study assesses the impact of different numbers of iterations per timestep and compares three distinct RANS turbulence models: k- ω SST, Spalart-Allmaras, and Realizable k- ε . The results show that finer mesh resolutions and smaller timesteps enhance accuracy in thrust and torque predictions. The k- ω SST model demonstrates the best balance between thrust generation and torque minimization, while the Spalart-Allmaras model underperforms in both categories. In addition, fewer iterations per timestep were found to be sufficient for convergence, reducing computational cost. Overall, this study provides a comprehensive evaluation of UAV propeller performance using CFD simulations.