Page 66 - Winter Issue 2018

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Computational Acoustics
formation of a new TSG, that would be a suitable and suf- The technical scope envisioned for the TSG includes the fol-
ﬁcient justiﬁcation for forming one. Given the increasingly lowing topics:
computational nature of acoustics and the sciences in gen- - Numerical methods for acoustic wave propagation, scat-
eral, and the interest of many members of the ASA in recent tering, interactions with structures and boundaries, ra-
developments in this area, it is important that the ASA deep- diation, and other acoustically related phenomena
en its support for CA—related activities. Particularly worth - Practical utilization of acoustical computations for en-
noting is that many of the signatories of the TSG petition gineering and noise control, and integration into other
were relatively young ASA members, which likely reﬂects simulations
the emphasis of their research projects and employment in- o Optimization, parallelization, and acceleration of compu-
terests. Hence the CA TSG should help the ASA to encour- tational algorithms
age and retain younger members. Many petition signatories - Validation, benchmarking, and uncertainty analysis in
also hail from countries other than the United States and computational models
Canada; thus the TSG can help expand the reach of the ASA o Computational learning methods, data analytics, and vi-
to researchers in other countries. sualization
Although most of the feedback we received regarding for- The ﬁrst of these topics includes various numerical methods
mation of a CA TSG was enthusiastic, some thoughtful ar- for solving differential and integral equations, for example,
guments were also made against the idea. The most frequent ﬁnite-difference methods, boundary-element methods,
was that computational acoustics is a tool that should be ﬁnite—element methods, parabolic equations, wavenumber
discussed within the scope of the existing TCs rather than integration, and ray tracing. It lies at the heart of how most
a proper research topic warranting focused discussions in researchers view computational acoustics. Some particular
a separate, specialized group. In response, it can be argued problems that have received strong interest in recent years
that computer science is now widely accepted as a legitimate include methods to efﬁciently handle complex boundaries
academic discipline, and in many other ﬁelds (e.g., ﬂuid dy- and irregular meshes (e.g., Thompson, 2006; Marburg and
namics, physics, and biology), computational techniques Nolte, 2008), time—domain formulations for attenuation and
are regarded as an important and rapidly expanding area impedance (e.g., Tam and Auriault, 1996), three-dimension-
of inquiry, distinct enough to be the subject of specialized al solutions for sound propagating in the ocean and atmo-
groups, meetings, and journals. Thus the formation of a CA sphere (e.g., Castor and Sturm, 2008), wave propagation and
TSG is really just a recognition of the important status of scattering in moving and inhomogeneous media (e.g., Osta-
computation across the spectrum of modern science. shev and Wilson, 2016), and nonlinear wave propagation
Currently’ CA topics are often discussed independently (sonic booms and explosions; e.g., Blanc-Benon et al., 2002).
within many of the TCs. This lack of interaction can be a Regarding the practical utilization of acoustical computa-
detriment to scientiﬁc progress because many computa- tions for engineering and noise control, a vital research area is
tional approaches have multiple applications. One pertinent how to efficiently capture complex physical phenomena with
example is the formulation of computational methods for limited computational resources. A prime example is model-
sound refraction and scattering, such as the parabolic equa- ing noise in complex urban environments where phenomena
tion, that have applications both underwater (e.g., Jensen such as reﬂections, shadowing by buildings, scattering and ab-
et al., 2011) and in the atmosphere (e.g., Salomons, 2012). sorption from facades and balconies, and distributed sound
Another example is ﬁnite—element methods for calculating sources are all important for accurate sound-level prediction.
sound ﬁelds in interior spaces, which are important in struc- Modeling of such phenomena in large urban spaces through
tural, engineering, and architectural acoustics (Thompson, direct numerical methods (e.g., ﬁnite differences or bound-
ZOO6; Marburg and Nolte, 2008; Vorléinder, 2013). The CA ary elements) can be prohibitive even with supercomputers,
TSG thus provides a forum for researchers to discuss recent although such models can be used to calibrate less intensive
advances in these and other topics crossing the existing TC empirical and heuristic models.
boundaries.
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E4 | Acnustics Thday | Winter 2018
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