Aeroacoustic Analysis of a Closely Installed Chevron Nozzle Jet using the High-Order Discontinuous Galerkin Method

In this paper, we use Large Eddy Simulations (LES) in combination with the Ffowcs Williams - Hawkings method to study the influence of chevrons on the flow field as well as the noise produced by a closely installed M = 0.6 jet. The LES simulations are performed with the spectral/hp element framework...

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Detalles Bibliográficos
Autores: Lindblad, D., Sherwin, S., Cantwell, C., Lawrence, J., Proença, A., Moragues, M.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2023
País:España
Institución:Basque Center for Applied Mathematics (BCAM)
Repositorio:BIRD. BCAM's Institutional Repository Data
OAI Identifier:oai:bird.bcamath.org:20.500.11824/1627
Acceso en línea:http://hdl.handle.net/20.500.11824/1627
Access Level:acceso abierto
Palabra clave:Chevron Nozzles, Roe Approximate Riemann Solver, Ffowcs Williams Hawkings Equation, Large Eddy Simulation, Navier Stokes Equations, Power Spectral Density, Laminar to Turbulent Transition, Acoustic Mach Number, Stagnation Temperature, Aircraft Noise
Descripción
Sumario:In this paper, we use Large Eddy Simulations (LES) in combination with the Ffowcs Williams - Hawkings method to study the influence of chevrons on the flow field as well as the noise produced by a closely installed M = 0.6 jet. The LES simulations are performed with the spectral/hp element framework Nektar++. Nektar++ uses the high-order discontinuous Galerkin method and an implicit scheme based on the matrix-free Newton-GMRES method to discretize the unfiltered Navier-Stokes equations in space and time, respectively. The far-field noise is computed using Antares. Antares solves the Ffowcs Williams - Hawkings equation for a permeable integration surface in the time-domain using a source-time dominant algorithm. The aerodynamic results show good agreement with experimental data obtained in the Doak Laboratory Flight Jet Rig, located at the University of Southampton. Some discrepancies are observed in terms of the far-field noise levels, especially for higher polar observer angles relative to the downstream jet axis. In terms of noise reduction potential, the simulations predict that the chevrons reduce the OASPL by 1dB compared to an installed round nozzle for all observers located on the unshielded side of the wing. This should be compared to the experiments, which predict a 1.5dB noise reduction for the same chevron nozzle.