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dc.contributor.author
Athari, Sahand
dc.contributor.supervisor
Girot, Christophe
dc.contributor.supervisor
Heutsehi, Kurt
dc.date.accessioned
2023-04-13T05:55:32Z
dc.date.available
2023-04-12T10:40:13Z
dc.date.available
2023-04-12T17:23:17Z
dc.date.available
2023-04-13T05:55:32Z
dc.date.issued
2023
dc.identifier.uri
http://hdl.handle.net/20.500.11850/607512
dc.identifier.doi
10.3929/ethz-b-000607512
dc.description.abstract
This doctoral thesis is focused on the auralisation of an urban street canyon with moving sound sources. The main result of this PhD is an auralisation tool based on a hybrid simulation of the acoustic field in a street canyon. Consider a person standing on the sidewalk or sitting on a balcony or at a terrace café. A car passes by in the street canyon, which represents certain façade geometries and materials. What will the person hear? The tool that is developed in this project answers this question. Possible auralisation variables include the speed of the car, number of cars, position and number of receivers, and complexity and materiality of the façades in the 3D street canyon design. The tool is based on a hybrid simulation. Results obtained from wave-based methods are hybridised with those obtained from geometric acoustics methods. For the wave-based part, the Finite Difference Time Domain (FDTD) method is used, and for the geometric acoustics part, Ray Tracing (RT) is used. FDTD is used to calculate the Impulse Response (IR) of the street canyon at lower frequencies where wave phenomena are more prominent, while RT is used to calculate the IR at higher frequencies. The hybrid IR is then obtained by means of signal filtering techniques. This hybrid IR covers the audible frequency range of the acoustic wave of interest between 20 Hz and 16 kHz. This IR gives us data about stationary sources and receivers. In order to use this data to model a moving source, the IR is obtained for several point sources along the path of the car pass-by. Once these IRs are calculated using the FDTD and RT methods and are hybridised, an interpolation strategy is used to create a smooth transition from each point source to the next by considering the direct sound and the reflections to represent the car’s motion in the street canyon. Lastly, these interpolated IRs are auralised. The output of the tool is audio files in the .wav format, which can be listened to via headphones. This way it is possible to hear a simulated version of what the pedestrian mentioned at the beginning of this text would hear. By considering different street canyon design scenarios including smooth walls, structured façades, or absorptive materials, this research provides simulation possibilities for the corresponding acoustic phenomena including specular reflection, surface scattering, absorption and diffraction. By creating results in different design scenarios including different façade geometries and materials and different listener positions, it is possible to compare the psychoacoustic consequences of each scenario in terms of preference. This thesis is part of the SNF-funded interdisciplinary research project “Urban Mining for Low Noise Roads and Optimised Design of Street Canyons”, and is a collaboration between the Chair of Landscape Architecture of Prof. Christophe Girot at ETH Zürich, the Acoustics and Noise Control Laboratory of Empa Dübendorf, the Road Engineering Laboratory of Empa Dübendorf, and the Chair of Ecological Systems Design at ETH Zürich. The overall project has different aspects, one of which is the acoustics aspect. The acoustics aspect of the overall project had two main parts: (1) addressing the optimised design of street canyons, and (2) addressing urban mining for low noise roads. Part (1) has led to the creation of the above-mentioned auralisation tool. Listening tests based on this tool have been developed and carried out, and the results are included in this thesis. These results show the preference of the subjects as well as their evaluation of the degree of realism of the auralisations. The plausibility and precision of this moving source auralisation tool as well as its capability to incorporate reflections from complex 3D façade geometries is the main contribution of this thesis to the urban acoustics community, architects, and urban designers. Part (2) includes the examination of potential effects of using urban-mined materials such as Crumb Rubber (CR), Polyethylene Terephthalate (PET), and Recycled Concrete Aggregate (RCA) in different asphalt mixtures by measuring their sound absorption coefficients. The results of these measurements are provided in the Appendix A. The measurements were done in the Acoustics and Noise Control Laboratory of Empa, Dübendorf, Switzerland.
en_US
dc.format
application/pdf
en_US
dc.language.iso
en
en_US
dc.publisher
ETH Zurich
en_US
dc.rights.uri
http://rightsstatements.org/page/InC-NC/1.0/
dc.subject
Acoustics
en_US
dc.subject
Urban design
en_US
dc.subject
Facade
en_US
dc.subject
Auralisation
en_US
dc.subject
Auralization
en_US
dc.subject
Simulation
en_US
dc.subject
Architecture
en_US
dc.title
A hybrid acoustics simulation of 3D urban street canyon design scenarios with multiple reflections used for auralising a moving sound source
en_US
dc.type
Doctoral Thesis
dc.rights.license
In Copyright - Non-Commercial Use Permitted
dc.date.published
2023-04-13
ethz.size
88 p.
en_US
ethz.code.ddc
DDC - DDC::6 - Technology, medicine and applied sciences::600 - Technology (applied sciences)
en_US
ethz.code.ddc
DDC - DDC::6 - Technology, medicine and applied sciences::690 - Buildings
en_US
ethz.identifier.diss
29050
en_US
ethz.publication.place
Zurich
en_US
ethz.publication.status
published
en_US
ethz.leitzahl
ETH Zürich::00002 - ETH Zürich::00012 - Lehre und Forschung::00007 - Departemente::02100 - Dep. Architektur / Dep. of Architecture::02667 - Institut Landschaft und Urbane Studien / Institute Urban and Landscape Studies::03578 - Girot, Christophe (emeritus) / Girot, Christophe (emeritus)
en_US
ethz.leitzahl
ETH Zürich::00002 - ETH Zürich::00012 - Lehre und Forschung::00007 - Departemente::02100 - Dep. Architektur / Dep. of Architecture::02655 - Netzwerk Stadt u. Landschaft ARCH u BAUG / Network City and Landscape ARCH and BAUG
*
ethz.leitzahl.certified
ETH Zürich::00002 - ETH Zürich::00012 - Lehre und Forschung::00007 - Departemente::02100 - Dep. Architektur / Dep. of Architecture::02667 - Institut Landschaft und Urbane Studien / Institute Urban and Landscape Studies::03578 - Girot, Christophe (emeritus) / Girot, Christophe (emeritus)
en_US
ethz.date.deposited
2023-04-12T10:40:14Z
ethz.source
FORM
ethz.eth
yes
en_US
ethz.availability
Open access
en_US
ethz.rosetta.installDate
2023-04-13T05:55:34Z
ethz.rosetta.lastUpdated
2024-02-02T21:36:19Z
ethz.rosetta.exportRequired
true
ethz.rosetta.versionExported
true
ethz.COinS
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