How dynamic growth of avenue trees affects particulate matter dispersion: CFD simulations in street canyons

Qin, Hongqiao; Hong, Bo; Huang, Boze; Cui, Xue; Zhang, Ting

doi:10.1016/j.scs.2020.102331

Cited by 37 publications

(10 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To improve the microclimate and street thermal comfort in summer especially during extremely hot weather, various factors should be combined, e.g., improved street wind condition [43], practical street orientation [28,36], and landscape planning [25,76] as suggested by Lai et al [77].…”

Section: Discussionmentioning

confidence: 99%

“…In-canyon vegetation exhibits a relatively larger cooling effect during daytime than at night [42]. Tree height, crown diameter, and volume are primary factors affecting the pedestrian level of particulate matter reduction ratio, whereas leaf area index (LAI) has a comparatively low influence [43]. However, trees block the airflow in street canyons, which leads to higher pollutant concentrations [44].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Study on Microclimate and Outdoor Thermal Comfort of Street Canyon Typology in Extremely Hot Weather—A Case Study of Busan, South Korea

Chang

Yoon

2022

Atmosphere

View full text Add to dashboard Cite

As cities are extremely vulnerable to the impacts of climate change, they are fundamental in addressing these changes. However, streets, which are external spaces accessed by citizens in daily life, play an important role in improving the urban environment and public health. This study considered Busan in South Korea as a case study to investigate street canyons, including street canyon geometries and tree configurations, of old, present, and new city centers. The influence of morphological factors on the microclimate and outdoor thermal comfort was evaluated using the ENVI-met program for extremely hot weather. Changes in the street width, street orientation, and street canyon aspect ratio had a significantly higher impact on the microclimate and thermal comfort index (p < 0.01). These results indicated that the orientation of the main street should be consistent with the prevailing wind direction of Busan. Further, the shading of adjacent buildings improved the outdoor thermal comfort and reduced the significance of tree configuration in deeper street canyons. In addition, tree height had a more significant impact on street environment than other tree configuration factors, especially when the tree height increased from 9 m to 12 m. We recommended that the thermal comfort level can be improved by dynamically adjusting the relationship between the planting distance and tree height in streets having shallow street canyons.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Numerical Study on Microclimate and Outdoor Thermal Comfort of Street Canyon Typology in Extremely Hot Weather—A Case Study of Busan, South Korea

Chang

Yoon

2022

Atmosphere

View full text Add to dashboard Cite

show abstract

“…This means that trees need a period of stability after planting. As the growth and stabilization of the trees progressed, active PM absorption, adsorption, blocking and deposition through trees slowly emerged [11,39,40]. The physiological stabilization of trees ensures that the PM reduction in the GB zone can be maintained continuously.…”

Section: Discussionmentioning

confidence: 99%

A 10-year Analysis on the Reduction of Particulate Matter at the Green Buffer of the Sihwa Industrial Complex

et al. 2021

View full text Add to dashboard Cite

Green buffer (GB) zones are designed to prevent the spread of air pollutants and odors from industrial complexes (ICs) to residential areas (RAs). We analyzed changes in the concentration of particulate matter (PM) and the number of high PM pollution days for 10 years after the GB was implemented, using the National Atmospheric Environmental Research Stations 2001–2018 dataset. We also performed field measurements of PM10 and PM2.5 from February 2018 to January 2019 to analyze the PM concentrations at human breathing height throughout the GB. Before GB implementation (2001–2006), PM10 in the RA was 9% higher than that in the IC. After GB zone implementation (2013–2018), PM10 in the RA was 11% lower than that of the IC. Furthermore, the PM concentration in the RA (slope = ∆Concentration/∆Time, −2.09) rapidly decreased compared to that in the IC (slope = −1.02) and the western coastal area (WCA) (slope = −1.55) over the 10-year period. At PM concentrations at human breathing height, PM10 and PM2.5 in the RA were lower than those in the IC by 27% and 26%, respectively. After GB implementation, the wind speed was positively correlated but SOx was negatively correlated with the PM reduction rate at a local scale. These results show that there was a reduction of PM during and after GB implementation, implying the need for proper management of GBs and continuous measure of pollutant sources at the green buffers of industrial complexes.

show abstract

“…(e.g., [46,50,56,61,67,70,72,73,82,83]). A total of 13 papers modelled the pollutant as a particulate matter (PM), which included both PM10 and PM2.5 [48,74,77,[84][85][86][87][88][89][90][91][92][93]. In addition, the pollutant in 3 studies consisted of both a gas and PM.…”

Section: Pollutant Typementioning

confidence: 99%

“…Meanwhile, some articles (e.g., [58,59,68,71,73,75,[94][95][96]) investigated the dispersion of pollutant from stack sources located on top of buildings, which is an equally important factor as it can negatively influence the air quality in the surrounding areas. In contrast, the pollutant in 3 studies [87,88,90] was injected into the computational domain from the inlet plane. Finally, a single study [97] explored the dispersion of a tracer gas released from the 3rd floor of a high-rise building.…”

Section: Source Of Emissionmentioning

confidence: 99%

Air Pollution Dispersion Modelling in Urban Environment Using CFD: A Systematic Review

et al. 2022

View full text Add to dashboard Cite

Air pollution is a global problem, which needs to be understood and controlled to ensure a healthy environment and inform sustainable development. Urban areas have been established as one of the main contributors to air pollution, and, as such, urban air quality is the subject of an increasing volume of research. One of the principal means of studying air pollution dispersion is to use computational fluid dynamics (CFD) models. Subject to careful verification and validation, these models allow for analysts to predict air flow and pollution concentration for various urban morphologies under different environmental conditions. This article presents a detailed review of the use of CFD to model air pollution dispersion in an urban environment over the last decade. The review extracts and summarises information from nearly 90 pieces of published research, categorising it according to over 190 modelling features, which are thematically systemised into 7 groups. The findings from across the field are critically compared to available urban air pollution modelling guidelines and standards. Among the various quantitative trends and statistics from the review, two key findings stand out. The first is that, despite the existence of best practice guidelines for pollution dispersion modelling, anywhere between 12% and 34% of the papers do not specify one or more aspects of the utilised models, which are required to reproduce the study. The second is that none of the articles perform verification and validation according to accepted standards. The results of this review can, therefore, be used by practitioners in the field of pollution dispersion modelling to understand the general trends in current research and to identify open problems to be addressed in the future.

show abstract

How dynamic growth of avenue trees affects particulate matter dispersion: CFD simulations in street canyons

Cited by 37 publications

References 72 publications

Numerical Study on Microclimate and Outdoor Thermal Comfort of Street Canyon Typology in Extremely Hot Weather—A Case Study of Busan, South Korea

Numerical Study on Microclimate and Outdoor Thermal Comfort of Street Canyon Typology in Extremely Hot Weather—A Case Study of Busan, South Korea

A 10-year Analysis on the Reduction of Particulate Matter at the Green Buffer of the Sihwa Industrial Complex

Air Pollution Dispersion Modelling in Urban Environment Using CFD: A Systematic Review

Contact Info

Product

Resources

About