The rapid emergence of Urban Air Mobility (UAM) demands accurate prediction and mitigation of noise generated by electric vertical take-off and landing (eVTOL) aircraft operating in complex urban environments. Among the various noise sources, the aerodynamic and acoustic response of rotors to unsteady inflow represents a major uncertainty in community-noise assessment and certification. This thesis investigates the aerodynamic and aeroacoustic behavior of a representative eVTOL rotor subjected to time-harmonic inflow disturbances, providing a detailed numerical framework to quantify how periodic gusts influence rotor performance, unsteady loading, and sound radiation.
The study employs a three-stage computational methodology using the open-source solver \\textit{OpenFOAM v2412} coupled with the \\textit{PSU-WOPWOP} acoustic post-processor. First, a baseline rotor simulation is conducted under uniform inflow to validate the computational model against experimental data from the Virginia Tech full-scale acoustic measurements of the Joby Aviation 2017 prototype rotor. The comparison of thrust, torque, and sound pressure levels demonstrates close agreement, confirming the accuracy of the selected Spalart--Allmaras Delayed Detached Eddy Simulation (SA-DDES) turbulence model. Second, a time-harmonic gust generator is implemented via a localized momentum-source formulation to create convected inflow disturbances with controlled amplitude and frequency, verified to maintain phase and amplitude coherence during propagation. Finally, gust--rotor interaction cases are performed for two inflow amplitudes, representing 10\\% and 30\\% perturbations of the mean velocity.
Results show that while mean thrust and torque remain nearly constant across gust intensities, the unsteady load fluctuations increase in thrust and torque, producing distinct spectral sidebands at the blade-passing frequency. Acoustic analysis reveals modest amplification of tonal components at the BPF, accompanied by slight attenuation of low-frequency radiation. The developed framework contributes to the broader goal of establishing predictive tools for urban aeroacoustic certification and noise-sensitive vehicle design.
","abstract_html":"<p>The rapid emergence of Urban Air Mobility (UAM) demands accurate prediction and mitigation of noise generated by electric vertical take-off and landing (eVTOL) aircraft operating in complex urban environments. Among the various noise sources, the aerodynamic and acoustic response of rotors to unsteady inflow represents a major uncertainty in community-noise assessment and certification. This thesis investigates the aerodynamic and aeroacoustic behavior of a representative eVTOL rotor subjected to time-harmonic inflow disturbances, providing a detailed numerical framework to quantify how periodic gusts influence rotor performance, unsteady loading, and sound radiation.</p> <p>The study employs a three-stage computational methodology using the open-source solver \\textit{OpenFOAM v2412} coupled with the \\textit{PSU-WOPWOP} acoustic post-processor. First, a baseline rotor simulation is conducted under uniform inflow to validate the computational model against experimental data from the Virginia Tech full-scale acoustic measurements of the Joby Aviation 2017 prototype rotor. The comparison of thrust, torque, and sound pressure levels demonstrates close agreement, confirming the accuracy of the selected Spalart--Allmaras Delayed Detached Eddy Simulation (SA-DDES) turbulence model. Second, a time-harmonic gust generator is implemented via a localized momentum-source formulation to create convected inflow disturbances with controlled amplitude and frequency, verified to maintain phase and amplitude coherence during propagation. Finally, gust--rotor interaction cases are performed for two inflow amplitudes, representing 10\\% and 30\\% perturbations of the mean velocity.</p> <p>Results show that while mean thrust and torque remain nearly constant across gust intensities, the unsteady load fluctuations increase in thrust and torque, producing distinct spectral sidebands at the blade-passing frequency. Acoustic analysis reveals modest amplification of tonal components at the BPF, accompanied by slight attenuation of low-frequency radiation. The developed framework contributes to the broader goal of establishing predictive tools for urban aeroacoustic certification and noise-sensitive vehicle design.</p>","abstract_has_math":false,"creators":["Voropayev, Vadim"],"institution":null,"degree_name":"Master of Science in Aerospace Engineering","degree_level":"Thesis - Open Access","degree_discipline":"Aerospace Engineering","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025-10-01T07:00:00Z","date_published":"2025-10-01T07:00:00Z","updated_at":"2026-07-27T19:26:22Z","subjects":["Aerodynamics","Aeroacoustics","CFD","High-Fidelity Simulations","Gust","Turbulence","DDES","Noise","Performance","Aerodynamics and Fluid Mechanics","Aeronautical Vehicles","Other Aerospace Engineering"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://commons.erau.edu/edt/950","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Voropayev, Vadim"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_discipline","label":"Discipline","values":["Aerospace Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - Open Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science in Aerospace Engineering"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Aerodynamics","Aeroacoustics","CFD","High-Fidelity Simulations","Gust","Turbulence","DDES","Noise","Performance","Aerodynamics and Fluid Mechanics","Aeronautical Vehicles","Other Aerospace Engineering"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://commons.erau.edu/edt/950"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The rapid emergence of Urban Air Mobility (UAM) demands accurate prediction and mitigation of noise generated by electric vertical take-off and landing (eVTOL) aircraft operating in complex urban environments. Among the various noise sources, the aerodynamic and acoustic response of rotors to unsteady inflow represents a major uncertainty in community-noise assessment and certification. This thesis investigates the aerodynamic and aeroacoustic behavior of a representative eVTOL rotor subjected to time-harmonic inflow disturbances, providing a detailed numerical framework to quantify how periodic gusts influence rotor performance, unsteady loading, and sound radiation.
The study employs a three-stage computational methodology using the open-source solver \\textit{OpenFOAM v2412} coupled with the \\textit{PSU-WOPWOP} acoustic post-processor. First, a baseline rotor simulation is conducted under uniform inflow to validate the computational model against experimental data from the Virginia Tech full-scale acoustic measurements of the Joby Aviation 2017 prototype rotor. The comparison of thrust, torque, and sound pressure levels demonstrates close agreement, confirming the accuracy of the selected Spalart--Allmaras Delayed Detached Eddy Simulation (SA-DDES) turbulence model. Second, a time-harmonic gust generator is implemented via a localized momentum-source formulation to create convected inflow disturbances with controlled amplitude and frequency, verified to maintain phase and amplitude coherence during propagation. Finally, gust--rotor interaction cases are performed for two inflow amplitudes, representing 10\\% and 30\\% perturbations of the mean velocity.
Results show that while mean thrust and torque remain nearly constant across gust intensities, the unsteady load fluctuations increase in thrust and torque, producing distinct spectral sidebands at the blade-passing frequency. Acoustic analysis reveals modest amplification of tonal components at the BPF, accompanied by slight attenuation of low-frequency radiation. The developed framework contributes to the broader goal of establishing predictive tools for urban aeroacoustic certification and noise-sensitive vehicle design.
"]},{"key":"dc:title","label":"Title","values":["High-Fidelity Modeling of eVTOL Rotor Unsteady Aerodynamic and Aeroacoustic Response to Time-Harmonic Gust"]}]}],"canonical_facts":{"dc:creator":["Voropayev, Vadim"],"dc:description.abstract":["The rapid emergence of Urban Air Mobility (UAM) demands accurate prediction and mitigation of noise generated by electric vertical take-off and landing (eVTOL) aircraft operating in complex urban environments. Among the various noise sources, the aerodynamic and acoustic response of rotors to unsteady inflow represents a major uncertainty in community-noise assessment and certification. This thesis investigates the aerodynamic and aeroacoustic behavior of a representative eVTOL rotor subjected to time-harmonic inflow disturbances, providing a detailed numerical framework to quantify how periodic gusts influence rotor performance, unsteady loading, and sound radiation.
The study employs a three-stage computational methodology using the open-source solver \\textit{OpenFOAM v2412} coupled with the \\textit{PSU-WOPWOP} acoustic post-processor. First, a baseline rotor simulation is conducted under uniform inflow to validate the computational model against experimental data from the Virginia Tech full-scale acoustic measurements of the Joby Aviation 2017 prototype rotor. The comparison of thrust, torque, and sound pressure levels demonstrates close agreement, confirming the accuracy of the selected Spalart--Allmaras Delayed Detached Eddy Simulation (SA-DDES) turbulence model. Second, a time-harmonic gust generator is implemented via a localized momentum-source formulation to create convected inflow disturbances with controlled amplitude and frequency, verified to maintain phase and amplitude coherence during propagation. Finally, gust--rotor interaction cases are performed for two inflow amplitudes, representing 10\\% and 30\\% perturbations of the mean velocity.
Results show that while mean thrust and torque remain nearly constant across gust intensities, the unsteady load fluctuations increase in thrust and torque, producing distinct spectral sidebands at the blade-passing frequency. Acoustic analysis reveals modest amplification of tonal components at the BPF, accompanied by slight attenuation of low-frequency radiation. The developed framework contributes to the broader goal of establishing predictive tools for urban aeroacoustic certification and noise-sensitive vehicle design.
"],"dc:identifier":["https://commons.erau.edu/edt/950"],"dc:subject":["Aerodynamics","Aeroacoustics","CFD","High-Fidelity Simulations","Gust","Turbulence","DDES","Noise","Performance","Aerodynamics and Fluid Mechanics","Aeronautical Vehicles","Other Aerospace Engineering"],"dc:title":["High-Fidelity Modeling of eVTOL Rotor Unsteady Aerodynamic and Aeroacoustic Response to Time-Harmonic Gust"],"thesis:degree_discipline":["Aerospace Engineering"],"thesis:degree_level":["Thesis - Open Access"],"thesis:degree_name":["Master of Science in Aerospace Engineering"]},"updated_at":"2026-07-27T19:26:22Z"}