All Outputs (15)

A comparison between the high-frequency Boundary Element Method and Surface-Based Geometrical Acoustics (2023)
Journal Article
Hargreaves, J. (2023). A comparison between the high-frequency Boundary Element Method and Surface-Based Geometrical Acoustics. https://doi.org/10.3397/in_2022_1005

The audible frequency range covers many octaves in which the wavelength changes from being large with respect to dominant features of a space to being comparatively much smaller. This makes numerical prediction of a space's acoustic response, e.g. fo... Read More about A comparison between the high-frequency Boundary Element Method and Surface-Based Geometrical Acoustics.

A time method version of the transfer matrix method (2021)
Journal Article
Steele, K., & Hargreaves, J. (2021). A time method version of the transfer matrix method. https://doi.org/10.25144/13761

Porous absorbers are ubiquitous in acoustics applications. They are, for example, widely used to control reverberation in rooms and cavities, or to provide attenuation in ducts. Because of this, they have attracted significant research effort to be... Read More about A time method version of the transfer matrix method.

A tutorial on the finite and boundary element methods in acoustics (2021)
Journal Article
Hargreaves, J. A. (2021). A tutorial on the finite and boundary element methods in acoustics. ˜The œJournal of the Acoustical Society of America (Online), 149(4_Supplement), A92-A92. https://doi.org/10.1121/10.0004613

The Finite Element Method (FEM) and Boundary Element Method (BEM) are established numerical simulation techniques that are widely used in Engineering, including in Acoustics. This tutorial lecture will give a brief tour of both methods, some discussi... Read More about A tutorial on the finite and boundary element methods in acoustics.

Investigation into the effects of the geometry in cone driven midrange horns & phase plugs (2020)
Journal Article
Macdonald, L., & Hargreaves, J. (2020). Investigation into the effects of the geometry in cone driven midrange horns & phase plugs. Proceedings of the Institute of Acoustics, 42(3), https://doi.org/10.25144/13367

Midrange horn loudspeakers are usually used in professional audio applications to improve efficiency and control directivity. Because traditional lumped parameter circuits do not model phase plugs or complexities of horn geometry after the expansion,... Read More about Investigation into the effects of the geometry in cone driven midrange horns & phase plugs.

Graduate programs in acoustics at the University of Salford, United Kingdom (2020)
Journal Article
Hargreaves, J. (2020). Graduate programs in acoustics at the University of Salford, United Kingdom. ˜The œJournal of the Acoustical Society of America (Online), 148(4), 2745. https://doi.org/10.1121/1.5147628

Salford is one of the UK's leading centers for research and teaching in acoustics and audio. The courses are delivered by a research-active academic team at the very pinnacle of the profession, with an attractive staff to student ratio. Our taught co... Read More about Graduate programs in acoustics at the University of Salford, United Kingdom.

A framework for auralization of boundary element method simulations including source and receiver directivity (2019)
Journal Article
Hargreaves, J., Rendell, L., & Lam, Y. (2019). A framework for auralization of boundary element method simulations including source and receiver directivity. ˜The œJournal of the Acoustical Society of America (Online), 145(4), 2625-2637. https://doi.org/10.1121/1.5096171

The Boundary Element Method (BEM) is a proven numerical prediction tool for computation of room acoustic transfer functions, as are required for auralization of a virtual space. In this paper it is validated against case studies drawn from the ‘Groun... Read More about A framework for auralization of boundary element method simulations including source and receiver directivity.

The wave-matching boundary integral equation - an energy approach to Galerkin BEM for acoustic wave propagation problems (2018)
Journal Article
Hargreaves, J., & Lam, Y. (2019). The wave-matching boundary integral equation - an energy approach to Galerkin BEM for acoustic wave propagation problems. Wave Motion, 87, 4-36. https://doi.org/10.1016/j.wavemoti.2018.07.003

In this paper, a new Boundary Integral Equation (BIE) is proposed for solution of the scalar Helmholtz equation. Applications include acoustic scattering problems, as occur in room acoustics and outdoor and underwater sound propagation. It draws toge... Read More about The wave-matching boundary integral equation - an energy approach to Galerkin BEM for acoustic wave propagation problems.

A transformation approach for efficient evaluation of oscillatory surface integrals arising in three-dimensional boundary element methods (2016)
Journal Article
boundary element methods. International Journal for Numerical Methods in Engineering, 108(2), 93-115. https://doi.org/10.1002/nme.5204

We propose a method for efficient evaluation of surface integrals arising in boundary element methods for three-dimensional Helmholtz problems (with real positive wavenumber k), modelling wave scattering and/or radiation in homogeneous media. To re... Read More about A transformation approach for efficient evaluation of oscillatory surface integrals arising in three-dimensional boundary element methods.

Workshop on numerical acoustic simulation and auralisation as built environment design consultation tools (2015)
Journal Article
Hargreaves, J., & Lam, Y. (2015). Workshop on numerical acoustic simulation and auralisation as built environment design consultation tools. Acoustics bulletin / Institute of Acoustics, Nov 15,

Extended version of an article appearing in the November 2015 issue of Acoustics Bulletin, the UK Institute of Acoustics magazine. Describes an EPSRC-funded workshop, which was co-hosted by Arup and the University of Salford. For more informatio... Read More about Workshop on numerical acoustic simulation and auralisation as built environment design consultation tools.

An energy interpretation of the Kirchhoff-Helmholtz boundary integral equation and its application to Sound Field synthesis (2014)
Journal Article
Hargreaves, J., & Lam, Y. (2014). An energy interpretation of the Kirchhoff-Helmholtz boundary integral equation and its application to Sound Field synthesis. Acta acustica united with Acustica, 100(5), 912-920. https://doi.org/10.3813/AAA.918770

Most spatial audio reproduction systems have the constraint that all loudspeakers must be equidistant from the listener, a property which is difficult to achieve in real rooms. In traditional Ambisonics this arises because the spherical harmonic func... Read More about An energy interpretation of the Kirchhoff-Helmholtz boundary integral equation and its application to Sound Field synthesis.

Simulating acoustic scattering from atmospheric temperature fluctuations using a k-space method (2014)
Journal Article
Hargreaves, J., Kendrick, P., & von Hünerbein, S. (2014). Simulating acoustic scattering from atmospheric temperature fluctuations using a k-space method. ˜The œJournal of the Acoustical Society of America (Online), 135(1), 82-92. https://doi.org/10.1121/1.4835955

This paper describes a numerical method for simulating far-field scattering from small regions of inhomogeneous temperature fluctuations. Such scattering is of interest since it is the mechanism by which acoustic wind velocity profiling devices (Dopp... Read More about Simulating acoustic scattering from atmospheric temperature fluctuations using a k-space method.

Subjective preference of modal control methods in listening rooms (2012)
Journal Article
Fazenda, B., Wankling, M., Hargreaves, J., Elmer, L., & Hirst, J. (2012). Subjective preference of modal control methods in listening rooms. Journal of the Audio Engineering Society, 60(5), 338-349

Methods to control the unwanted effects of low-frequency modes in critical listening rooms range from complex signal processing to the positioning of loudspeakers and listeners. A rigorous scientific experiment has been conducted to evaluate the perc... Read More about Subjective preference of modal control methods in listening rooms.

Low frequency sound propagation in activated carbon (2012)
Journal Article
Bechwati, F., Avis, M., Bull, D., Cox, T., Hargreaves, J., Moser, D., …Venegas, R. (2012). Low frequency sound propagation in activated carbon. https://doi.org/10.1121/1.4725761

Activated carbon can adsorb and desorb gas molecules onto and off its surface. Research has examined whether this sorption affects low frequency sound waves, with pressures typical of audible sound, interacting with granular activated carbon. Imped... Read More about Low frequency sound propagation in activated carbon.

A transient boundary element method for acoustic scattering from mixed regular and thin rigid bodies (2009)
Journal Article
Hargreaves, J., & Cox, T. (2009). A transient boundary element method for acoustic scattering from mixed regular and thin rigid bodies. Acta acustica united with Acustica, 95(4), 678-689. https://doi.org/10.3813/AAA.918196

Boundary Element Methods (BEMs) may be used to predict the scattering of sound by obstacles, which has accelerated the prototyping of new room acoustic treatments such as diffusers. Unlike the more popular frequency domain method, the time domain BE... Read More about A transient boundary element method for acoustic scattering from mixed regular and thin rigid bodies.

A transient boundary element method model of Schroeder diffuser scattering using well mouth impedance (2008)
Journal Article
Hargreaves, J., & Cox, T. (2008). A transient boundary element method model of Schroeder diffuser scattering using well mouth impedance. ˜The œJournal of the Acoustical Society of America (Online), 124(5), 2942-2951. https://doi.org/10.1121/1.2982420

Room acoustic diffusers can be used to treat critical listening environments to improve sound quality. One popular class is Schroeder diffusers, which comprise wells of varying depth separated by thin fins. This paper concerns a new approach to ena... Read More about A transient boundary element method model of Schroeder diffuser scattering using well mouth impedance.