Urban morphology as a passive strategy in promoting outdoor air quality

Hassan, Asmaa M.; elmokadem, ashraf; Megahed, Naglaa A.; Eleinen, Osama Mahmoud Abo

doi:10.1016/j.jobe.2020.101204

Cited by 40 publications

(21 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The diagonal linear configurations in models one, two, three, and four promoted recirculation regions through increased localized airflow momentum and turbulence intensity, which led to higher normalized air velocities, which confirmed in Refs. [ 64 , 70 ]. Furthermore, this also led to a decreased average droplet diameter and droplet deposition [ 76 ].…”

Section: Discussionmentioning

confidence: 99%

“…Such an enhancement can significantly promote crossing the main vortex, with secondary vortices divergence, and convergence of the shear layer vortices, besides shape the vertical turbulent velocities, as well turbulent diffusion, as indicated in Refs. [ 64 , 104 ].…”

Section: Discussionmentioning

confidence: 99%

“…Building upon advances in computational resources, in particular CFD, an integrated modeling approach using numerical modeling [ 64 ] is employed to investigate the influence of the design of urban public seats on COVID-19 transmission in urban public spaces. CFD has been applied in a wide variety of fields, engineering flow analysis, building structure design, urban wind flow prediction, and air pollution dispersion to urban design, and urbanscape planning [ 65 , 66 ], enabling urbanscape designers, urban designers, and planners to develop design alternatives [ [67] , [68] , [69] ].…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

COVID-19 and urban spaces: A new integrated CFD approach for public health opportunities

Hassan

Megahed

2021

Building and Environment

Self Cite

View full text Add to dashboard Cite

Safe urban public spaces are vital owing to their impacts on public health, especially during pandemics such as the ongoing COVID-19 pandemic. Urban public spaces and urbanscape elements must be designed with the risk of viral transmission in mind. This work therefore examines how the design of urbanscape elements can be revisited to control COVID-19 transmission dynamics. Nine proposed models of urban public seating were thus presented and assessed using a transient three-dimensional computational fluid dynamics (CFD) model, with the Eulerian–Lagrangian method and discrete phase model (DPM). The proposed seating models were evaluated by their impact on the normalized air velocity, the diameter of coughing droplets, and deposition fraction. Each of the proposed models demonstrated an increase in the normalized velocity, and a decrease in the deposition fraction by >29%. Diagonal cross linear and curved triangle configurations demonstrated an improved airflow momentum and turbulent flow, which decreased the droplets deposition fraction by 68%, thus providing an improved, healthier urban public seating option.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

COVID-19 and urban spaces: A new integrated CFD approach for public health opportunities

Hassan

Megahed

2021

Building and Environment

Self Cite

View full text Add to dashboard Cite

show abstract

“…Several studies -mainly based on CFD models, including LES approaches have thus focused on the performance of air pollution dispersion by green infrastructures in open areas and street canyons, even characterizing the capacity of parked vehicles to reduce pedestrian exposure to pollutants (see review article in Abhijith et al, 2017). Also, the link between the morphology of urban buildings, the dispersion of emissions and air quality is often apprehended through CFD models (Hassan et al, 2020). At an even more operational level, LUR models (based on the spatial analysis of air quality data)…”

Section: Contribution Of Modelling To Policy Making and Urban Management Strategiesmentioning

confidence: 99%

Advances in Air Quality Research – Current and Emerging Challenges

Sokhi

Moussiopoulos

Baklanov

et al. 2021

Preprint

View full text Add to dashboard Cite

Abstract. This review provides a community’s perspective on air quality research focussing mainly on developments over the past decade. The article provides perspectives on current and future challenges as well as research needs for selected key topics. While this paper is not an exhaustive review of all research areas in the field of air quality, we have selected key topics that we feel are important from air quality research and policy perspectives. After providing a short historical overview, this review focuses on improvements in characterising sources and emissions of air pollution, new air quality observations and instrumentation, advances in air quality prediction and forecasting, understanding interactions of air quality with meteorology and climate, exposure and health assessment, and air quality management and policy. In conducting the review, specific objectives were (i) to address current developments that push the boundaries of air quality research forward, (ii) to highlight the emerging prominent gaps of knowledge in air quality research and (iii) and to make recommendations to guide the direction for future research within the wider community. This review also identifies areas of particular importance for air quality policy. The original concept of this review was borne at the International Conference on Air Quality 2020 (held online due to the COVID 19 restrictions during 18–26 May 2020), but the article incorporates a wider landscape of research literature within the field of air quality science. On air pollution emissions the review highlights, in particular, the need to reduce uncertainties in emissions from diffuse sources, particulate matter chemical components, shipping emissions and the importance of considering both indoor and outdoor sources. There is a growing need to have integrated air pollution and related observations from both ground based and remote sensing instruments, including especially those on satellites. The research should also capitalize on the growing area of lower cost sensors, while ensuring a quality of the measurements which are regulated by guidelines. Connecting various physical scales in air quality modelling is still a continual issue, with cities being affected by air pollution gradients at local scales and by long range transport. At the same time, one should allow for the impacts from climate change on a longer timescale. Earth system modelling offers considerable potential by providing a consistent framework for treating scales and processes, especially where there are significant feedbacks, such as those related to aerosols, chemistry and meteorology. Assessment of exposure to air pollution should consider both the impacts of indoor and outdoor emissions, as well as apply more sophisticated, dynamic modelling approaches. With particulate matter being one of the most important pollutants for health, research is indicating the urgent need to understand, in particular, the role of particle number and chemical components in terms of health impact, which in turn requires improved emission inventories and models for predicting high resolution distributions of these metrics over cities. The review also examines, how air pollution management needs to adapt to the above-mentioned new challenges and briefly considers the implications from the COVID-19 pandemic for air quality. Finally, we provide recommendations for air quality research and support for policy.

show abstract

“…There are also some differences in the research technologies associated with WWR in urban planning and building science. In urban planning, WWR studies are mostly conducted using CFD software (Computational Fluid Dynamics) [22][23][24], which is capable of simulating the thermal behavior of various materials under various morphological conditions, calculating their influences on local wind speed, air temperature, and relative humidity [25][26][27]. Nevertheless, the CFD-based software packages are not advanced in their ability to calculate energy consumption.…”

Section: Introductionmentioning

confidence: 99%

Evaluating the Effect of Window-to-Wall Ratios on Cooling-Energy Demand on a Typical Summer Day

Zheng

Bedra

et al. 2021

IJERPH

View full text Add to dashboard Cite

The window-to-wall ratio (WWR) significantly affects the indoor thermal environment, causing changes in buildings’ energy demands. This research couples the “Envi-met” model and the “TRNSYS” model to predict the impact of the window-to-wall ratio on indoor cooling energy demands in south Hunan. With the coupled model, “Envi-met + TRNSYS”, fixed meteorological parameters around the exterior walls are replaced by varied data provided by Envi-met. This makes TRNSYS predictions more accurate. Six window-to-wall ratios are considered in this research, and in each scenario, the electricity demand for cooling is predicted using “Envi-met + TRNSYS”. Based on the classification of thermal perception in south Hunan, the TRNSYS predictions of the electricity demand start with 30 °C as the threshold of refrigeration. The analytical results reveal that in a 6-storey residential building with 24 households, in order to maintain the air temperature below 30 °C, the electricity required for cooling buildings with 0% WWR, 20% WWR, 40% WWR, 60% WWR, 80% WWR, and 100% WWR are respectively 0 KW·h, 19.6 KW·h, 133.7 KW·h, 273.1 KW·h, 374.5 KW·h, and 461.9 KW·h. This method considers the influence of microclimate on the exterior wall and improves the accuracy of TRNSYS in predicting the energy demand for indoor cooling.

show abstract

Urban morphology as a passive strategy in promoting outdoor air quality

Cited by 40 publications

References 44 publications

COVID-19 and urban spaces: A new integrated CFD approach for public health opportunities

COVID-19 and urban spaces: A new integrated CFD approach for public health opportunities

Advances in Air Quality Research – Current and Emerging Challenges

Evaluating the Effect of Window-to-Wall Ratios on Cooling-Energy Demand on a Typical Summer Day

Contact Info

Product

Resources

About