Numerical fluid simulations of a Multi-rotor propeller. A validation study for experimental propeller data and identification of vortex sources

Abstract

For centuries, propellers have been used to propel ships, in the beginning through water, and later they began being used to propel aircraft through the air. Propellers increase the pressure in the fluid and are beneficial for low-speed aerospace applications. Today, a common use for propellers is in drones, where the concern for noise emissions arises due to their popularity and in-city use. Therefore, this thesis studied the aerodynamic performance of a 14x8-inch propeller by Advanced Precision Composites and the vortices generated by it using Computational Fluid Dynamics simulations solving steady-state Reynolds Averaged Navier-Stokes equations. The results from these simulations are then compared to experimental data from the University of Illinois Urbana-Champaign.

The results of the simulations showed the model most closely following the experimental results for low advance ratios with an error for efficiency around 10%. The simulations were performed with a rotational rate of 4038 rpm and inlet velocities ranging from 10.4 m/s to 17.7 m/s. The simulation model also showed the most common occurrence of vortices being from the hub and the tip of the blades. A reduction in tip vortices would be beneficial to reduce the aero-acoustic noise generated by the propeller.