The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon
Thesis (PhD. (Mechanical Engineering))
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| Format: | Thesis |
| Language: | English |
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Universiti Teknologi Malaysia
2024
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| Online Access: | https://openscience.utm.my/handle/123456789/1468 |
| _version_ | 1824446308789780480 |
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| author | Muhammad Yazid, Muhammad Noor Afiq Witri |
| author_facet | Muhammad Yazid, Muhammad Noor Afiq Witri |
| author_sort | Muhammad Yazid, Muhammad Noor Afiq Witri |
| collection | OpenScience |
| description | Thesis (PhD. (Mechanical Engineering)) |
| first_indexed | 2025-02-19T01:13:06Z |
| format | Thesis |
| id | oai:openscience.utm.my:123456789/1468 |
| institution | Universiti Teknologi Malaysia - OpenScience |
| language | English |
| last_indexed | 2025-02-19T01:13:06Z |
| publishDate | 2024 |
| publisher | Universiti Teknologi Malaysia |
| record_format | dspace |
| spelling | oai:openscience.utm.my:123456789/14682024-12-17T09:00:41Z The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon Muhammad Yazid, Muhammad Noor Afiq Witri Meteorology and climatology Air pollution Environmental engineering of buildings Urban forestry Thesis (PhD. (Mechanical Engineering)) Deterioration of outdoor air quality and harsh outdoor microclimate in a street canyon posed a serious threat to the urban dweller’s physical and mental health. The main purpose of this study was to investigate the combined effects of presence of trees, different diurnal heating situations and different street ratios on wind speed, pollutant dispersion and air temperature in a street canyon by means of Computational Fluid Dynamics (CFD). Initially, investigation on the suitability of the existing wind tunnel were carried out. Wind tunnel results shows that the formation of a thick turbulent boundary layer had a good vertical mean velocity profile except for the turbulent intensity profile; hence an alternative wind tunnel study was adopted as benchmark data for CFD. Validation study of numerical simulation of wind flow in a street canyon under the influence of thermal effects shows that the prediction by the large eddy simulation (LES) against wind tunnel data was better than the Reynolds-averaged Navier-Stokes (RANS) at steady state and the unstable RANS (URANS). Qualitative comparison between the parameters that were adopted for parametric study against previous studies were adequately representing a street canyon at full scale. Parametric study shows that the street aspect ratio was identified as the dominant factor compared to the presence of trees in reducing wind speed and air quality in a street canyon because of low momentum transfer from ambient wind into lower region of street canyon. Furthermore, the presence of trees in a street canyon under different diurnal heating situations is an ideal condition to achieve simultaneous low air temperature and better air quality where tree shade can reduce the surface area being heated up by the sun whilst the buoyancy force produced in street canyon by diurnal heating situations can compensate for the wind reduction caused by the trees. Faculty of Mechanical Engineering. 2024-12-17T00:20:39Z 2024-12-17T00:20:39Z 2015 Thesis Dataset https://openscience.utm.my/handle/123456789/1468 en application/pdf application/pdf application/pdf application/pdf Universiti Teknologi Malaysia |
| spellingShingle | Meteorology and climatology Air pollution Environmental engineering of buildings Urban forestry Muhammad Yazid, Muhammad Noor Afiq Witri The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon |
| title | The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon |
| title_full | The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon |
| title_fullStr | The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon |
| title_full_unstemmed | The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon |
| title_short | The effects of heating and tree configurations on pollutant dispersion and air temperature in Street Canyon |
| title_sort | effects of heating and tree configurations on pollutant dispersion and air temperature in street canyon |
| topic | Meteorology and climatology Air pollution Environmental engineering of buildings Urban forestry |
| url | https://openscience.utm.my/handle/123456789/1468 |
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