Impact of Composition of Exterior Wall on the Temperature in the Room

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.820.159 ◽

2016 ◽

Vol 820 ◽

pp. 159-164

Author(s):

Kamil Binek ◽

Juraj Žilinský

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Urban Areas ◽

Office Buildings ◽

Exterior Wall ◽

Correct Orientation ◽

Development Area ◽

Warm Room

Nowadays, residential as well as office buildings are faced to high demands in terms of thermal comfort, which can be defined as a feeling of satisfaction with the thermal aspects of environment, in which the person does not feel hot or cold . This definition means, that the user does not wish hotter or colder environment. [1] This condition is essential to ensure both during winter and summer. Because the staying in a very warm room is uncomfortable, it is necessary to find a solution to cut off overheating of the building. In urban areas, dense development area and areas with lack of green, this temperature increases very quickly and you cannot absorb it. Because of this, it should be considered to design the correct orientation of the habitat of building. In this article we want to highlight the changes in air temperature during the day.

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Investigating the relationship between variation of greenhouse gases concentrations and humidex

E3S Web of Conferences ◽

10.1051/e3sconf/20187411004 ◽

2018 ◽

Vol 74 ◽

pp. 11004 ◽

Cited By ~ 1

Author(s):

Anies Ma’rufatin ◽

Haryoto Kusnoputranto ◽

Kardono

Keyword(s):

Greenhouse Gases ◽

Thermal Comfort ◽

Air Temperature ◽

Urban Areas ◽

Negative Relationship ◽

Co2 Concentration ◽

Comfort Level ◽

Human Thermal Comfort ◽

Ch4 Concentration ◽

The Relationship

The increasing greenhouse gases (GHGs) in the atmosphere contribute to increasing average temperature earth’s surface. This research investigated relationship between variation of GHGs and human thermal comfort based on humidity index (humidex). This study applied humidex, an indices to assess the thermal comfort. The analysis was done by examining the observational data from two different monitoring stations in Serpong and Bogor. The result showed that the average CO2 concentration per month ranged between 422 and 453 ppm in Serpong, whereas in Bogor the average CO2 concentration per month was 413-426 ppm. The average CH4 concentration per month variation in Serpong was 2.05-2.65 ppm. While in Bogor, the average CH4 concentration per month variation ranged between 1.92 and 2.08 ppm. The difference of GHGs concentration in each location might be influenced by meteorological parameters and environmental characteristics. The comfort level according to humidex in Serpong was 30.5-41.5 whereas in Bogor was 29.4-38.5. The correlation between GHGs concentration and air temperature in urban areas in both stations showed a significant and strong but negative relationship. The relationship between GHGs concentration and humidex was indirectly indicated by the relationship of GHGs concentration on air temperature as indicator of humidex.

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Climate change and built environment - the role of urban greenery as a mitigation strategy in Greek urban areas

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/899/1/012018 ◽

2021 ◽

Vol 899 (1) ◽

pp. 012018

Author(s):

D Apostolopoulou ◽

S Tsoka

Keyword(s):

Climate Change ◽

Thermal Comfort ◽

Air Temperature ◽

Urban Areas ◽

Heat Waves ◽

Well Being ◽

Climatic Conditions ◽

Mitigation Strategy ◽

Urban Greenery

Abstract Extreme thermal conditions and heat waves, as a result of global warming, have increased in recent years. Especially in the Mediterranean area, cities face higher temperatures during summer months which severely affect thermal comfort and citizens’ well-being. In this context, this study aims to evaluate the role of urban greenery as a mitigation strategy and focuses on its effect towards the improvement of the urban microclimate and thermal comfort under extreme summer conditions. To this aim, a typical square, located in Athens, Greece, has been chosen as a case study. The microclimatic conditions are evaluated for its present state and after an increase of 20% of soil surface and 30% of trees, while both current (i.e., 2020) and future summer climatic conditions (for the year 2060) are examined. It was also proposed that all the soil surfaces would be covered in grass. The potential air temperature, mean radiant temperature and surface temperature are analysed by simulation means, using the ENVI-met microclimate simulation tool. The results of this study showed that increasing the vegetation ratio inside the study area contributes to considerably lower surface temperatures, while a significant reduction on mean radiant and air temperature at the pedestrian level is also achieved, forming better microclimate conditions. Urban greenery is an important factor for healthy and resilient cities. Its presence can provide lower temperatures in the pedestrian level during summer months, reforming the microclimate. The outcomes of this study can be used by urban planners and stakeholders to improve environmentally urban areas, mitigate the results of climate change, and create resilient cities.

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Building Integrated Shading and Building Applied Photovoltaic System Assessment in the Energy Performance and Thermal Comfort of Office Buildings

Sustainability ◽

10.3390/su10124670 ◽

2018 ◽

Vol 10 (12) ◽

pp. 4670 ◽

Cited By ~ 6

Author(s):

Georgios Martinopoulos ◽

Anna Serasidou ◽

Panagiota Antoniadou ◽

Agis M. Papadopoulos

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Urban Areas ◽

Specific Energy Consumption ◽

Energy Performance ◽

Office Buildings ◽

Photovoltaic System ◽

Energy Status ◽

Building Stock ◽

Consumption Rates

Non-residential and more specifically office buildings are, nowadays, an integral part of the building stock and milestones of urban areas in most of the developed and developing countries all over the world. Compared to other building types, office buildings present some of the highest specific energy consumption rates. In the present study, a typical nine-story office is assessed for a number of different building integrated retrofitting measures. Measurements of indoor environmental conditions were used in order to validate the developed simulation model of the building in EnergyPlus. Then, a number of different building integration options for photovoltaic systems and shading options are examined, in order to evaluate the best option in terms of indoor air quality, thermal comfort and energy consumption. The amount of electricity produced can meet 65% of the building’s annual electricity requirements, while the shading options can reduce energy requirements by as much as 33%. Although this in not a value that can be dismissed easily, it becomes clear that further—and more deeply aiming—measures are needed, if the building is to achieve near zero energy status.

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Simulation of the thermal comfort conditions of urban areas: a case study in Kyiv

Geology Geography Ecology ◽

10.26565/2410-7360-2019-51-13 ◽

2019 ◽

Keyword(s):

Heat Stress ◽

Thermal Comfort ◽

Air Temperature ◽

Urban Areas ◽

Meteorological Parameters ◽

Urban Spaces ◽

Weather Station ◽

Adaptation Measures ◽

Bioclimatic Indices ◽

The City

Formulation of the problem. Studies of bioclimate of a territory are aimed at determining the favorable and adverse impacts of various climatic factors and their combinations on the human body. Complex urban morphology has a significant impact on microclimate and, accordingly, on thermal comfort of a person in such an environment. The height of buildings, street orientation, and distance between buildings alter the solar energy inlet, affect thermal regime, transform the wind speed and direction at the street level. Studies of the bioclimatic conditions of urban areas during the warm season are highly relevant as they provide an opportunity to evaluate human thermal sensations in the city, as well as the potential effectiveness of adaptation measures to heat stress (architectural measures and measures based on the use of green areas and water bodies). The purpose of the article. The aim of this research is to simulate the bioclimate of an urban environment to determine the human thermal load in summer months based on modern bioclimatic indices and software. Methods. For the purpose of this study, a part of the territory of the Osokorky residential area of Kyiv was selected. To get values of the main meteorological parameters of the researched area, a three-dimensional, prognostic, microscale model ENVI-met was used. ENVI-met pertains to the CFD-models (computation fluid dynamics model) and is designed for microscales with a horizontal resolution from 0.5 to 10 m and with a time step of 10 seconds as maximum. The PET calculation was performed using the RayMan model. Results. A clear hot summer day (04 August 2017) was chosen for the simulation. The simulation was performed from 6:00 EEST on 4 August till 6:00 EEST the next day (output interval – 1 hour). The simulation results show that the values of the main meteorological parameters (air temperature and humidity, wind characteristics) and physiologically equivalent temperature differ significantly within urban spaces, even across small areas. The amplitudes of PET value were maximum in the daytime and made 12°–15°C. The decrease in the amplitude of the air temperature within the researched area in the evening and night hours led to a notable decrease in the PET amplitude to 2°–3°C. The analysis of the simulated PET values for the researched area confirmed that the residents of the urban areas experience the most intense heat stress while staying in the open asphalted areas during the daytime. The duration of the period with comfortable conditions during the researched day was very short – from 22:00 EEST through midnight. The range of the daily course of PET values at different points of the researched area varied from 19.4° (at point No. 7) to 37.1°C (at point No. 5 located in the well courtyard). Based on the PET values simulated for the researched area and for CAWS Kyiv was found the significant differences between thermal comfort conditions within the complex urban spaces and at the weather station. Therefore, the values of bioclimatic indices simulated based on the weather station data can not be applied with any approximation to solve scientific and applied tasks that require information on the bioclimate at particular points in the urbanized environment. To solve such tasks, it is recommended to apply modern methods – ENVI-met and RayMan models. Scientific novelty and practical significance. For the first time in Ukraine, microclimate and thermal comfort conditions within the complex urban environment has been simulated using ENVI-met and RayMan models. The results of such simulation can be used to choose heat adaptation measures which would help to increase the comfort of the urban areas. The simulation of microclimate and thermal comfort conditions of some parts of the city territory is important stage of design of the buildings, in order to choose the optimal location for buildings and trees and to create the most comfortable conditions for people.

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URBAN FACADE GEOMETRY ON OUTDOOR COMFORT CONDITIONS: A REVIEW

INDONESIAN JOURNAL OF URBAN AND ENVIRONMENTAL TECHNOLOGY ◽

10.25105/urbanenvirotech.v4i1.7151 ◽

2020 ◽

Vol 4 (1) ◽

pp. 45

Author(s):

Elahe Mirabi ◽

Nasrollahi Nazanin

Keyword(s):

Thermal Comfort ◽

Urban Areas ◽

Natural Ventilation ◽

Flow Behavior ◽

Air Flow ◽

Urban Geometry ◽

Wide Range ◽

Low Energy Buildings ◽

Outdoor Comfort ◽

Solar Access

Designing urban facades is considered as a major factor influencing issues such as natural ventilation of buildings and urban areas, radiations in the urban canyon for designing low-energy buildings, cooling demand for buildings in urban area, and thermal comfort in urban streets. However, so far, most studies on urban topics have been focused on flat facades without details of urban layouts. Hence, the effect of urban facades with details such as the balcony and corbelling on thermal comfort conditions and air flow behavior are discussed in this literature review. Aim: This study was carried out to investigate the effective factors of urban facades, including the effects of building configuration, geometry and urban canyon’s orientation. Methodology and Results: According to the results, the air flow behavior is affected by a wide range of factors such as wind conditions, urban geometry and wind direction. Urban façade geometry can change outdoor air flow pattern, thermal comfort and solar access. Conclusion, significance and impact study: In particular, the geometry of the facade, such as indentation and protrusion, has a significant effect on the air flow and thermal behavior in urban facades and can enhance outdoor comfort conditions. Also, Alternation in façade geometry can affect pedestrians' comfort and buildings energy demands.

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Flood alleviation in a heavily urbanized area – Kai Tak Nullah, Hong Kong

Water Practice & Technology ◽

10.2166/wpt.2012.096 ◽

2012 ◽

Vol 7 (4) ◽

Author(s):

Alan K. L. Chan ◽

Colin K. C. Wong ◽

Robin H. N. Lee ◽

Mike W. H. Cho

Keyword(s):

Hong Kong ◽

Public Engagement ◽

Urban Areas ◽

Hydraulic Modelling ◽

The Public ◽

Design Considerations ◽

Urbanized Area ◽

Development Area ◽

The Government ◽

Exercise Design

The existing Kai Tak Nullah flows from Po Kong Village Road along Choi Hung Road and Tung Tau Estate into Kai Tak Development Area before discharging into the Victoria Harbour. Historically its upstream has been subject to flooding under storm conditions and this has had serious repercussions for the adjacent urban areas. A study has been commissioned by the Drainage Services Department of the Government of the Hong Kong Special Administrative Region (HKSAR), China to investigate the flood mechanisms and to provide flood alleviation measures by improving the capacity of the Kai Tak Nullah. In addition to flood alleviation, there is a strong public aspiration to rehabilitate the Kai Tak Nullah by a comparatively natural river design. Since the Kai Tak Nullah is located within a heavily urbanized area, traffic and environmental impacts are also highly concerned. The final flood alleviation scheme has thus had to strike a balance among the aforesaid factors with assistance from the hydraulic modelling utilizing InfoWorks Collection Systems (CS) software. This paper presents the public engagement exercise, design considerations, methodologies, and recommendations regarding the reconstruction and rehabilitation of the Kai Tak Nullah.

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Reducing outdoor air temperature, improving thermal comfort, and saving buildings’ cooling energy demand in arid cities – Cool paving utilization

Sustainable Cities and Society ◽

10.1016/j.scs.2021.102762 ◽

2021 ◽

Vol 68 ◽

pp. 102762

Author(s):

Amir Aboelata

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Energy Demand ◽

Outdoor Air ◽

Cooling Energy Demand

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Biomimicry-Based Strategies for Urban Heat Island Mitigation: A Numerical Case Study under Tropical Climate

Biomimetics ◽

10.3390/biomimetics6030048 ◽

2021 ◽

Vol 6 (3) ◽

pp. 48

Author(s):

Kevin Araque ◽

Paola Palacios ◽

Dafni Mora ◽

Miguel Chen Austin

Keyword(s):

Thermal Comfort ◽

Urban Heat Island ◽

Urban Areas ◽

Outdoor Thermal Comfort ◽

Base Case ◽

Heat Island ◽

Urban Heat ◽

Historical Heritage ◽

Pet Index ◽

Radiant Temperature

In recent years, demographic growth has caused cities to expand their urban areas, increasing the risk of overheating, creating insurmountable microclimatic conditions within the urban area, which is why studies have been carried out on the urban heat island effect (UHI) and its mitigation. Therefore, this research aims to evaluate the cooling potential in the application of strategies based on biomimicry for the microclimate in a historical heritage city of Panama. For this, three case studies (base case, case 1, and case 2) of outdoor thermal comfort were evaluated, in which the Envi-met software was used to emulate and evaluate the thermal performance of these strategies during March (highest temperature month) and October (rainier month). The strategies used were extracted from the contrast of zebra skin, human skin, evaporative cooling, and ant skin. The results showed a reduction of 2.8 °C in the air temperature at 11:00, the radiant temperature decreased by 2.2 °C, and the PET index managed to reduce the thermal comfort indicator among its categories. The importance of thinking based on biomimicry in sustainable strategies is concluded; although significant changes were obtained, high risks of discomfort persist due to the layout and proximity of the building.

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Quantifying the Independent Influences of Land Cover and Humidity on Microscale Urban Air Temperature Variation in Hot Summer: Methods of Path Analysis and Genetic SVR

Atmosphere ◽

10.3390/atmos11121377 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1377

Author(s):

Weifang Shi ◽

Nan Wang ◽

Aixuan Xin ◽

Linglan Liu ◽

Jiaqi Hou ◽

...

Keyword(s):

Relative Humidity ◽

Land Cover ◽

Path Analysis ◽

Temperature Variation ◽

Direct Effect ◽

Air Temperature ◽

Urban Areas ◽

Support Vector ◽

Urban Air ◽

Air Temperatures

Mitigating high air temperatures and heat waves is vital for decreasing air pollution and protecting public health. To improve understanding of microscale urban air temperature variation, this paper performed measurements of air temperature and relative humidity in a field of Wuhan City in the afternoon of hot summer days, and used path analysis and genetic support vector regression (SVR) to quantify the independent influences of land cover and humidity on air temperature variation. The path analysis shows that most effect of the land cover is mediated through relative humidity difference, more than four times as much as the direct effect, and that the direct effect of relative humidity difference is nearly six times that of land cover, even larger than the total effect of the land cover. The SVR simulation illustrates that land cover and relative humidity independently contribute 16.3% and 83.7%, on average, to the rise of the air temperature over the land without vegetation in the study site. An alternative strategy of increasing the humidity artificially is proposed to reduce high air temperatures in urban areas. The study would provide scientific support for the regulation of the microclimate and the mitigation of the high air temperature in urban areas.

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