High-fidelity numerical analysis and optimisation of ducted propeller aerodynamics and acoustics

Parametric study of aerodynamic performance of equivalent ducted/un-ducted rotors

“…For the ducted rotor, there is a low noise window slightly after the rotor disk passage for the ducted rotor, which is due to the duct shielding and the altered acoustic directivity. The duct tends to redirect the acoustic waves towards the axial direction [17]. This feature agrees well with our previous near-field acoustic study based on high-fidelity CFD solutions [17].…”

“…The same grid topologies and simulation strategies were used in previous studies of ducted/open rotors in Refs [13,17], where grid sensitivity studies, using the same solver as this work, were also conducted. The grid sensitivity studies suggested that a total of about 12 million cells for one third of the computational domain would be more than adequate for mesh convergence.…”

“…We have also assumed infinite duct impedance for simplification. Similar approaches were adopted for noise predictions for ducted fans [17,32] and by Dighe et.al. [30] for ducted wind turbines.…”

“…[33][34][35][36]. It has also been used in previous simulation and optimisation studies of ducted rotors [13,17]. The numerical validation and performance analysis of the baseline ducted rotor design in the current work, i.e.…”

“…Numerical optimisation of the ducted rotor designs can also be noted [16,17]. However, due to geometries, relative motions, and complex flow features, the high-fidelity CFD modelling of ducted rotors with blades resolved remains challenging.…”