On thermally forced flows in urban street canyons
During sunny days with periods of low synoptic wind, buoyancy forces can play a critical role on the air flow, and thus on the dispersion of pollutants in the built urban environments. Earlier studies provide evidence that when a surface inside an urban street canyon is at a higher temperature than...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Springer Netherlands
2016
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| Online Access: | http://hdl.handle.net/1721.1/104088 https://orcid.org/0000-0002-5631-7256 https://orcid.org/0000-0002-8362-4761 |
| _version_ | 1826189461898133504 |
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| author | Magnusson, S. Dallman, A. Entekhabi, D. Britter, R. Norford, L. Fernando, H. J. S. Entekhabi, Dara Britter, Rex E. Norford, Leslie Keith |
| author2 | Massachusetts Institute of Technology. Department of Architecture |
| author_facet | Massachusetts Institute of Technology. Department of Architecture Magnusson, S. Dallman, A. Entekhabi, D. Britter, R. Norford, L. Fernando, H. J. S. Entekhabi, Dara Britter, Rex E. Norford, Leslie Keith |
| author_sort | Magnusson, S. |
| collection | MIT |
| description | During sunny days with periods of low synoptic wind, buoyancy forces can play a critical role on the air flow, and thus on the dispersion of pollutants in the built urban environments. Earlier studies provide evidence that when a surface inside an urban street canyon is at a higher temperature than that of local ambient air, buoyancy forces can modify the mechanically-induced circulation within the canyons (i.e., gaps between buildings). The aspect ratio of the urban canyon is a critical factor in the manifestation of the buoyancy parameter. In this paper, computational fluid dynamics simulations are performed on urban street canyons with six different aspect ratios, focusing on the special case where the leeward wall is at a greater temperature than local ambient air. A non-dimensional measure of the influence of buoyancy is used to predict demarcations between the flow regimes. Simulations are performed under a range of buoyancy conditions, including beyond those of previous studies. Observations from a field experiment and a wind tunnel experiment are used to validate the results. |
| first_indexed | 2024-09-23T08:15:27Z |
| format | Article |
| id | mit-1721.1/104088 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T08:15:27Z |
| publishDate | 2016 |
| publisher | Springer Netherlands |
| record_format | dspace |
| spelling | mit-1721.1/1040882022-09-30T08:39:22Z On thermally forced flows in urban street canyons Magnusson, S. Dallman, A. Entekhabi, D. Britter, R. Norford, L. Fernando, H. J. S. Entekhabi, Dara Britter, Rex E. Norford, Leslie Keith Massachusetts Institute of Technology. Department of Architecture Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Massachusetts Institute of Technology. Department of Urban Studies and Planning Magnusson, S. Entekhabi, Dara Britter, Rex E. Norford, Leslie Keith During sunny days with periods of low synoptic wind, buoyancy forces can play a critical role on the air flow, and thus on the dispersion of pollutants in the built urban environments. Earlier studies provide evidence that when a surface inside an urban street canyon is at a higher temperature than that of local ambient air, buoyancy forces can modify the mechanically-induced circulation within the canyons (i.e., gaps between buildings). The aspect ratio of the urban canyon is a critical factor in the manifestation of the buoyancy parameter. In this paper, computational fluid dynamics simulations are performed on urban street canyons with six different aspect ratios, focusing on the special case where the leeward wall is at a greater temperature than local ambient air. A non-dimensional measure of the influence of buoyancy is used to predict demarcations between the flow regimes. Simulations are performed under a range of buoyancy conditions, including beyond those of previous studies. Observations from a field experiment and a wind tunnel experiment are used to validate the results. Singapore. National Research Foundation (Singapore-MIT Alliance for Research and Technology’s Center for Environmental Sensing and Modeling) 2016-08-30T22:23:59Z 2016-08-30T22:23:59Z 2014-04 2013-09 2016-05-23T12:08:17Z Article http://purl.org/eprint/type/JournalArticle 1567-7419 1573-1510 http://hdl.handle.net/1721.1/104088 Magnusson, S. et al. “On Thermally Forced Flows in Urban Street Canyons.” Environmental Fluid Mechanics 14.6 (2014): 1427–1441. https://orcid.org/0000-0002-5631-7256 https://orcid.org/0000-0002-8362-4761 en http://dx.doi.org/10.1007/s10652-014-9353-4 Environmental Fluid Mechanics Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ Springer Science+Business Media Dordrecht application/pdf Springer Netherlands Springer Netherlands |
| spellingShingle | Magnusson, S. Dallman, A. Entekhabi, D. Britter, R. Norford, L. Fernando, H. J. S. Entekhabi, Dara Britter, Rex E. Norford, Leslie Keith On thermally forced flows in urban street canyons |
| title | On thermally forced flows in urban street canyons |
| title_full | On thermally forced flows in urban street canyons |
| title_fullStr | On thermally forced flows in urban street canyons |
| title_full_unstemmed | On thermally forced flows in urban street canyons |
| title_short | On thermally forced flows in urban street canyons |
| title_sort | on thermally forced flows in urban street canyons |
| url | http://hdl.handle.net/1721.1/104088 https://orcid.org/0000-0002-5631-7256 https://orcid.org/0000-0002-8362-4761 |
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