Numerical studies of the outdoor wind environment and thermal comfort at pedestrian level in housing blocks with different building layout patterns and trees arrangement

This paper presents a study of the effects of wind-induced airflow through the urban built layout pattern using statistical analysis. This study investigates the association between typically enclosed office building layout patterns and the wind environment. First of all, this study establishes an ideal site model of 200 m × 200 m and obtains four typical multi-story enclosed office building group layouts, namely the multi-yard parallel opening, the multi-yard returning shape opening, the overall courtyard parallel opening, and the overall courtyard returning shape opening. Then, the natural ventilation performance of different building morphologies is further evaluated via the computational fluid dynamics (CFD) simulation software Phoenics. This study compares wind speed distribution at an outdoor pedestrian height (1.5 m). Finally, the natural ventilation performance corresponding to the four layout forms is obtained, which showed that the outdoor wind environment of the multi-yard type is more comfortable than the overall courtyard type, and the degree of enclosure of the building group is related to the advantages and disadvantages of the outdoor wind environment. The quantitative relevance between building layout and wind environment is examined, according to which the results of an ameliorated layout proposal are presented and assessed by Phoenics. This research could provide a method to create a livable urban wind environment.

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Analysis of the influence of cooling jets on the wind and thermal environment in football stadiums in hot climates

Building Services Engineering Research and Technology ◽

10.1177/0143624419894803 ◽

2019 ◽

Vol 41 (5) ◽

pp. 561-585 ◽

Cited By ~ 1

Author(s):

Fangliang Zhong ◽

John K Calautit ◽

Ben R Hughes

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Air Conditioning ◽

Thermal Environment ◽

Thermal Conditions ◽

Optimized Design ◽

Outdoor Temperature ◽

World Cup ◽

Wind Environment ◽

The Spectator

After winning the bid of the FIFA’s World Cup 2022, Qatar is facing the greatest challenges in terms of minimizing substantial energy consumptions for air-conditioning of stadiums and maintaining aero-thermal comfort for both players and spectators inside stadiums. This paper presents the results of temperature distributions and wind environment of the original stadium under the hot-humid climate and improvements on them for optimized scenarios of cooling jets. A combined computational fluid dynamics and building energy simulation approach was used to analyse the cooling performance and energy consumption per match of cooling air jets for 10 scenarios with different supply velocities, supply temperatures and locations of jets. The optimal scenario is to employ vertical jets above the upper tiers at supply temperature of 20°C and velocities of 2–12 m/s, integrated with horizontal jets of the same temperature at the lower tiers with 4 m/s and around the pitch with 7 m/s. This scenario can maintain the spectator tiers at an average temperature of 22°C and reduce the maximum predicted percentage of dissatisfied of thermal comfort from the original 100% to 63% for the pitch and 19% for the tiers, respectively. In terms of the energy consumption for the air-conditioning system per match, compared with one of the 2010 South Africa World Cup stadiums Royal Bafokeng stadium which consumed approximately 22.8 MWh energy for air-conditioning in winter (highest outdoor temperature 24.4°C), the maximum energy consumption of the optimal scenario in November (highest outdoor temperature 34.2°C) can reach 108 MWh. In addition, the spectator zones with scenario 8 have the potential to be resilient to the seasonal change of outdoor temperature if slight modifications of the supply velocities and precise temperature control on the spectator zones are applied. Moreover, the configurations presented in this paper can be used as a foundation of jets arrangement for future stadium retrofits in the hot climates. Practical application: This study assesses the aero-thermal conditions of a case study stadium under the hot climate of Qatar and explores the potential of applying cooling jets with different supply velocities, supply temperatures and their locations on the enhancement of both thermal and wind environment of spectator tiers and pitch. The assessment of the original stadium indicates that the ascending curved roof structure impedes the fresh air entering into the stadium and results in an asymmetric temperature distribution on the spectator tiers. The optimized design suggests a combination of vertical jets under the roof and both three arrays of horizontal jets at lower tiers and around pitch for future stadium optimizations in hot climates. It also recommends enhancing the thermal conditions on the pitch by optimizing the velocity of horizontal jets around the pitch. Moreover, the future design of the exact stadiums to be resilient to the seasonal changing outdoor temperature can be implemented based on scenario 8.

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Analysis of the Wind Environment to Improve the Thermal Comfort in the Colonnade Space of a Qilou Street Based on the Relative Warmth Index

Sustainability ◽

10.3390/su11164402 ◽

2019 ◽

Vol 11 (16) ◽

pp. 4402 ◽

Cited By ~ 1

Author(s):

Xianfeng Huang ◽

Zhen Lu ◽

Zhixiang Zhuang

Keyword(s):

Wind Speed ◽

Thermal Comfort ◽

Architectural Design ◽

Thermal Environment ◽

Transitional Space ◽

Wind Environment ◽

Warmth Index ◽

Research Findings ◽

Building Components ◽

Computational Fluid Dynamics Cfd

By analyzing measurements of the thermal environment of a qilou (arcade building) street, this study used the relative warmth index (RWI) to evaluate the thermal comfort in the colonnade space of a qilou. The analysis of the influence of the temperature, humidity, and wind speed on the thermal comfort in the colonnade space of a qilou street was conducted, and it was shown that the ambient wind speed had a strong influence on the RWI, indicating that a proper increase in the wind speed positively affected thermal comfort in this space. Then, this study also analyzed the effects of different forms of qilou streets on the wind environment by employing computational fluid dynamics (CFD) and summarized the architectural design measures that can improve the thermal comfort, including adopting back chamfer, street gaps, and the appropriate sizing of building components. It was concluded that the wind environment of a qilou could be optimized in terms of these measures, and the average RWI value decreased by 0.06, effectively enhancing the thermal comfort in the colonnade space. The research findings are applicable toward designing a thermally comfortable environment in the transitional space.

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The Study of Building Indoor and Outdoor Wind Environment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.2592 ◽

2012 ◽

Vol 482-484 ◽

pp. 2592-2595 ◽

Cited By ~ 1

Author(s):

Zhong Hua Tang ◽

Ri Chao Liu ◽

De Bao Lei

Keyword(s):

Numerical Simulation ◽

Wind Field ◽

Indoor Environment ◽

Natural Ventilation ◽

High Quality ◽

Wind Environment ◽

Building Height ◽

Building Layout ◽

Indoor And Outdoor

Through FLUENT numerical simulation, this paper is aimed on studying the influence of outdoor wind environment on indoor environment. We found that building height, building layout format and opening format in the wall are significant impacted on indoor natural ventilation. At the three-fourth height of building, if the building layout and housing opening is stagger, it can get high-quality indoor natural ventilation and more evenly indoor wind field.

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A lining for the Thermal Comfort of Trekking Boots – Experimental and Numerical Studies

Research Journal of Textile and Apparel ◽

10.1108/rjta-15-03-2011-b006 ◽

2011 ◽

Vol 15 (3) ◽

pp. 50-61 ◽

Cited By ~ 2

Author(s):

M. Neves ◽

P. Arezes ◽

C.P. Leão ◽

S. Teixeira

Keyword(s):

Thermal Comfort ◽

Raw Materials ◽

Subjective Evaluation ◽

Objective Evaluation ◽

Physiological Model ◽

Thermal Discomfort ◽

Human Foot ◽

Second Stage ◽

Numerical Studies ◽

Physical Task

In this paper, a study on the design and development of functional shoe linings that are thermally comfortable is presented. The comfort of foot wear, in this case, trekking boots, that is perceived by the user greatly depends on the ability of the boot to maintain the foot surface in an equilibrium state in terms of thermo-physiological comfort (Schols et al., 2004). This is related to the capacity of removing the moisture that results from transpiration away from the foot surface. With these premises in mind, a study on the development of new lining constructions using different raw materials has been conducted. As far as methodology is concerned, this study involves two different stages. The first stage includes an objective evaluation of the thermal comfort of the boots. This stage involves several tasks, including the conception and development of the fabrics to be used in the inner layer of the boots and the development of a thermo-physiological model of the human foot, in order to simulate the temperature and moisture behavior in the developed fabrics. The second stage consists of a subjective evaluation of thermal comfort using prototypes of the developed boots. A subjective evaluation assessment was done through a questionnaire, in which the study subjects are able to indicate where they experience thermal discomfort in the foot, as well as a laboratory physical task used to simulate the “real” use of the boots.

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