Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating
Our study employed large-eddy simulation (LES) based on a one-equation subgrid-scale model to investigate the flow field and pollutant dispersion characteristics inside urban street canyons. Unstable thermal stratification was produced by heating the ground of the street canyon. Using the Boussinesq...
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| Format: | Article |
| Language: | en_US |
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Springer-Verlag
2013
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| Online Access: | http://hdl.handle.net/1721.1/77998 https://orcid.org/0000-0002-5631-7256 https://orcid.org/0000-0002-8362-4761 |
| _version_ | 1826208751644835840 |
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| author | Koh, Tieh Yong Norford, Leslie Keith Liu, Chun-Ho Entekhabi, Dara Leung, Dennis Y. C. Li, Xianxiang Britter, Rex E |
| author2 | Massachusetts Institute of Technology. Department of Architecture |
| author_facet | Massachusetts Institute of Technology. Department of Architecture Koh, Tieh Yong Norford, Leslie Keith Liu, Chun-Ho Entekhabi, Dara Leung, Dennis Y. C. Li, Xianxiang Britter, Rex E |
| author_sort | Koh, Tieh Yong |
| collection | MIT |
| description | Our study employed large-eddy simulation (LES) based on a one-equation subgrid-scale model to investigate the flow field and pollutant dispersion characteristics inside urban street canyons. Unstable thermal stratification was produced by heating the ground of the street canyon. Using the Boussinesq approximation, thermal buoyancy forces were taken into account in both the Navier–Stokes equations and the transport equation for subgrid-scale turbulent kinetic energy (TKE). The LESs were validated against experimental data obtained in wind-tunnel studies before the model was applied to study the detailed turbulence, temperature, and pollutant dispersion characteristics in the street canyon of aspect ratio 1. The effects of different Richardson numbers (Ri) were investigated. The ground heating significantly enhanced mean flow, turbulence, and pollutant flux inside the street canyon, but weakened the shear at the roof level. The mean flow was observed to be no longer isolated from the free stream and fresh air could be entrained into the street canyon at the roof-level leeward corner. Weighed against higher temperature, the ground heating facilitated pollutant removal from the street canyon. |
| first_indexed | 2024-09-23T14:11:03Z |
| format | Article |
| id | mit-1721.1/77998 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T14:11:03Z |
| publishDate | 2013 |
| publisher | Springer-Verlag |
| record_format | dspace |
| spelling | mit-1721.1/779982022-09-28T19:05:23Z Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating Koh, Tieh Yong Norford, Leslie Keith Liu, Chun-Ho Entekhabi, Dara Leung, Dennis Y. C. Li, Xianxiang Britter, Rex E 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 Singapore-MIT Alliance in Research and Technology (SMART) Li, Xian-Xiang Britter, Rex E. Norford, Leslie Keith Entekhabi, Dara Our study employed large-eddy simulation (LES) based on a one-equation subgrid-scale model to investigate the flow field and pollutant dispersion characteristics inside urban street canyons. Unstable thermal stratification was produced by heating the ground of the street canyon. Using the Boussinesq approximation, thermal buoyancy forces were taken into account in both the Navier–Stokes equations and the transport equation for subgrid-scale turbulent kinetic energy (TKE). The LESs were validated against experimental data obtained in wind-tunnel studies before the model was applied to study the detailed turbulence, temperature, and pollutant dispersion characteristics in the street canyon of aspect ratio 1. The effects of different Richardson numbers (Ri) were investigated. The ground heating significantly enhanced mean flow, turbulence, and pollutant flux inside the street canyon, but weakened the shear at the roof level. The mean flow was observed to be no longer isolated from the free stream and fresh air could be entrained into the street canyon at the roof-level leeward corner. Weighed against higher temperature, the ground heating facilitated pollutant removal from the street canyon. Singapore-MIT Alliance for Research and Technology. Center for Environmental Sensing and Monitoring 2013-03-27T13:55:02Z 2013-03-27T13:55:02Z 2010-08 2009-12 Article http://purl.org/eprint/type/JournalArticle 0006-8314 1573-1472 http://hdl.handle.net/1721.1/77998 Li, Xian-Xiang et al. “Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating.” Boundary-Layer Meteorology 137.2 (2010): 187–204. https://orcid.org/0000-0002-5631-7256 https://orcid.org/0000-0002-8362-4761 en_US http://dx.doi.org/10.1007/s10546-010-9534-8 Boundary - Layer Meterology Creative Commons Attribution-Noncommercial http://creativecommons.org/licenses/by-nc/3.0/ application/pdf Springer-Verlag Springer |
| spellingShingle | Koh, Tieh Yong Norford, Leslie Keith Liu, Chun-Ho Entekhabi, Dara Leung, Dennis Y. C. Li, Xianxiang Britter, Rex E Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating |
| title | Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating |
| title_full | Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating |
| title_fullStr | Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating |
| title_full_unstemmed | Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating |
| title_short | Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating |
| title_sort | large eddy simulation of flow and pollutant transport in urban street canyons with ground heating |
| url | http://hdl.handle.net/1721.1/77998 https://orcid.org/0000-0002-5631-7256 https://orcid.org/0000-0002-8362-4761 |
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