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Showing 1 to 20 of 21 for “"Computational aeroacoustics"”.
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Numerical techniques for computational aeroacoustics
… of aerodynamic noise is considered following the Computational Aeroacoustics approach which is based on direct numerical simulation of the sound field. In the region of sound generation, the unsteady airflow is computed separately from the sound using Computational Fluid Dynamics (CFD) codes. …
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Adaptive mesh refinement for computational aeroacoustics
… of Philosophy ADAPTIVE MESH REFINEMENT FOR COMPUTATIONAL AEROACOUSTICS by Xun Huang<br/>This thesis describes a parallel block-structured adaptive mesh refinement (AMR) method that is employed to solve some computational aeroacoustic problems with the aim of improving the computational …
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Defect correction methods for computational aeroacoustics
… The framework is extended to the area of Computational Aeroacoustics (CAA) where sound waves generated by the pressure fluctuations are typically several orders of magnitude smaller than the pressure variations in the main flow field that accounts for flow acceleration. A decomposition of …
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A multidomain spectral method for computational aeroacoustics
This thesis presents a method for computational aeroacoustics, primarily aimed at computing sound propagation in, and radiation from, turbofan inlets. The physics of sound propagation is modeled by the system of partial differential equations that describe conservation of mass, momentum and energy …
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A source-extraction based coupling method for computational aeroacoustics
… background mean flow. The accuracy of computational results from these model problems is very encouraging when reasonable computational mesh sizes and time steps are used in both the CFD solver and the acoustic solver. Several applications of the source-extraction based coupling method …
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Computational aeroacoustics via linearized Euler equations in the frequency domain
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1993.
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TIME-CONSERVATIVE FINITE-VOLUME METHOD WITH LARGE-EDDY SIMULATION FOR COMPUTATIONAL AEROACOUSTICS
… schemes commonly regarded as inadequate for computational aeroacoustic (CAA) applications.
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Analysis and Application of Perfectly Matched Layer Absorbing Boundary Conditions for Computational Aeroacoustics
… of electromagnetics. The idea was extended to Computational Aeroacoustics in 1996, when Hu applied the method to Euler's equations. Since that time much of the work done on PML in the field of acoustics has been specific to the case where mean flow is perpendicular to a boundary, with an …
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The Linearized Euler Equations for Predicting Supersonic Jet Noise of a Rectangular Jet Using OpenFOAM
… for OpenFOAM. OpenFOAM is an open-source Computational Fluid Dynamics (CFD) package that is widely used by industry and academia. The LEE’s are a set of equations used in Computational Aeroacoustics (CAA). The LEE’s can solve for the acoustic solution directly and quickly. The solver …
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Adjoint-based monopole synthesis of sound sources with complex directivities
… Euler equations are solved by means of computational aeroacoustics (CAA). To efficiently compute reference sound fields, an analytical complex directivity point source (CDPS) model is embedded into the existing architecture of the CAA solver, which enables a decomposition of the …
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Random-vortex-particle methods applied to broadband fan interaction noise
… the suitability of a stochastic method for computational aeroacoustics, the specific objective being to devise a stochastic method to generate synthetic turbulence and combine it with the linearised Euler equations to predict broadband fan interaction noise. In modern turbofan designs …
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Physics-based aeroacoustic modelling of bluff-bodies
… of landing gear noise prediction tools. A computational approach was adopted so that the noise generating physics of the problem could be captured. Governing laws were solved numerically to predict the noise source characteristics and the resulting acoustic far-field. Three-dimensional …
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Scaling finite difference methods in large eddy simulation of jet engine noise to the petascale: numerical methods and their efficient and automated implementation
… As a relatively new field of research in computational fluid dynamics (CFD), computational aeroacoustics (CAA) prediction of jet engine noise based on large eddy simulation (LES) is a robust and accurate tool that complements the existing theoretical and experimental approaches. In order …
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Perfectly Matched Layer Absorbing Boundary Conditions for the Discrete Velocity Boltzmann-BGK Equation
… 1996, progress made in the application of PML to Computational Aeroacoustics (CAA) includes linearized Euler equations with non-uniform mean flow, non-linear Euler equations, flows with an arbitrary mean flow direction, and non-linear clavier-Stokes equations. Although Boltzmann-BGK methods have …
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Computation and control of flow-induced noise behind a circular cylinder using an acoustic analogy approach
The computational aeroacoustics (CAA) research, which focuses on predicting acoustics by means of advanced numerical techniques, has recently gained a great deal of progress. In most applications, the prediction of both the sound source and its far-field propagation is necessary as required by …
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Unsteady aerodynamics using high-order methods
… of this project, the combination of high order Computational Aeroacoustics (CAA) numerical schemes, non-reflecting boundary conditions and DES constituted a state of the art approach to the simulation of unsteady compressible flow phenomena at low Mach numbers. In the numerical study of 2D …
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Investigating the Feasibility and Stability for Modeling Acoustic Wave Scattering Using a Time-Domain Boundary Integral Equation with Impedance Boundary Condition
… noise is a major objective in the field of computational aeroacoustics. When designing next generation quiet and environmentally friendly aircraft, it is important to be able to accurately and efficiently predict the acoustic scattering by an aircraft body from a given noise source. Acoustic …
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Resolvent-based framework for jet noise reduction of a low bypass ratio coannular nozzle
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2025-08-01
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DGM-FD: A Finite Difference Scheme Based on the Discontinuous Galerkin Method
… is important in many areas of study such as computational aero-acoustics (CAA). While dissipation and dispersion errors influence the accuracy of a method, efficiency can be assessed by convergence rates and effective adaptability to different mesh structures. Finite difference and finite …
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High Fidelity Open Rotor Noise Prediction
As improving the performance of turbofan designs becomes increasingly difficult, manufacturers are looking to new technologies for the next generation of jet engines. An ``open rotor'' replaces the fan of the turbofan with a set of external rotors. This has the potential to offer a significant …
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