GPU-Accelerated CABARET Simulations of Distributed Propulsion for UAM
Hussain A. ABID, Igor SOLNTSEV, Andrea RAPISARDA, Hassan A. ABID, Sergey A. KARABASOV, E. DE PAOLA, Luana Georgiana STOICA, Giorgia CAPOBIANCHI, Alessandro DI MARCO, R. CAMUSSI
Abstract. Urban Air Mobility (UAM) vehicles rely on distributed propulsion (DP) to achieve efficiency, control authority, and compact integration with lifting surfaces. The close spacing of multiple rotors, however, intensifies installation effects that elevate tonal and broadband noise. This work presents a high-fidelity Large Eddy Simulation (LES) study using the CABARET method on rotating meshes to quantify aeroacoustic and aerodynamic sensitivities of a three-propeller DP configuration. The campaign varies: (i) central-rotor axial position (∆x = {-0.2Db,0,+0.2Db}), (ii) inter-rotor phase angle (0°,45°,90°,135°), and(iii) blade trailing-edge geometry (baseline vs. sawtooth serrations). Band-limited overall sound pressure level (BL OASPL) is evaluated on a probe plane under the array between the 1st and 6th blade-passing frequencies. Key findings are: (a) serrations consistently reduce area-averaged and maximum BL OASPL by up to 2.4 dB, most notably around 90◦ phase; (b) moving the central rotor closer to the wing increases thrust coefficient by ≈ 7.8%, indicating a beneficial rotor–wing interaction akin to ground effect; (c) the aerodynamic penalty of serrations is modest and attributable to effective area loss near the tip. Flow visualizations show serrations disrupt spanwise coherence and trailing-edge vortex organization, explaining the observed acoustic benefits. The results highlight the importance of joint optimization of geometry and phasing to deliver quieter, efficient DP systems for UAM.
Keywords
Distributed Propulsion, Urban Air Mobility, CABARET Method, Large Eddy Simulation, Rotating Meshes, Aeroacoustics, Trailing-Edge Serrations
Published online 7/20/2026, 7 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Hussain A. ABID, Igor SOLNTSEV, Andrea RAPISARDA, Hassan A. ABID, Sergey A. KARABASOV, E. DE PAOLA, Luana Georgiana STOICA, Giorgia CAPOBIANCHI, Alessandro DI MARCO, R. CAMUSSI, GPU-Accelerated CABARET Simulations of Distributed Propulsion for UAM, Materials Research Proceedings, Vol. 69, pp 564-570, 2026
DOI: https://doi.org/10.21741/9781644904251-101
The article was published as article 101 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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