Papers by Keyword: Urban Heat Island

Abstract: The urban surface contains a large amount of asphalt concrete pavement, which is also one of the main causes of the urban heat island effect. This study aims to explore the effect of BOFS on radiative cooling when applied to asphalt concrete pavement, and to review it as strategies to mitigate the urban heat island effect. This study chooses the density grading certified by TAF commonly used by road design units at present. Setting up thermometers on the actual construction site, the temperature of each layer would be measured. It is hoped that through comparison at actual on-site paving of BOFS pellets and natural pellets, the difference in effectiveness in radiant cooling can be evaluated. The results show that BOFS pellets for road paving have significant potential for radiative cooling.

Abstract: Green roof is a vegetated roof system to minimize the negative impacts of urbanization. This systematic review focuses on trends in green roof applications and materials for green buildings published between 2000 and 2022, using the PRISMA method. The database search was conducted using Scopus, obtaining 90 relevant articles. The articles were categorized based on the green roof applications (hydrological performance, stormwater quality, and urban heat island (UHI)) and the materials used, yielding 45 articles each on commercial materials and recycled waste. The highest number of articles were published in the “Journal of Building Engineering.” Between 2012 and 2022, it is observed that recycled waste was the most widely researched material within the published literature. Research interest in utilizing recycled waste material for green buildings has substantially increased. The use of waste material for green buildings shows a promising advancement in improving stormwater management i.e., in hydrological performance and quality, as well as reducing UHI.

Abstract: Traditional impermeable pavements such as asphalt have dark surfaces and high thermal inertia. During hot weather, they tend to absorb and store solar radiation, which promotes the development of urban heat islands (UHI). Furthermore, permeable pavements are effective in mitigating the urban heat island effect via evaporative cooling. There are many studies in the literature on the hydraulic and mechanical characteristics of permeable pavements, but a few studies focus on the impact of evaporative cooling of these pavements. In this study, 3 types of permeable pavements based on pozzolan, recycled rubber and polyurethane resin were studied during 3 hot days. The objective was to quantify the cooling effect in these innovative permeable pavements compared to a traditional impermeable asphalt pavement. The results of this experiment show that the cooling effect in the new types of draining pavements can last up to two days in the weather conditions of this experiment compared to the traditional asphalt pavement. The evaporation rate and surface temperature of permeable pavements vary in opposite directions. In addition, evaporation in pervious pavements is controlled by the availability of water near the surface. This study is a preliminary step in the design of pavements that contribute to the valorization of rubber waste, to the stormwater management and to the reduction of the effects of urban heat islands during heat waves.

Abstract: This article wants to introduce modular green roof systems and their usage in the world as well as in the Czech Republic, because green roofs are now used more than they have been constructed in any era in the history. Their construction is almost same as it was in previous centuries, so the obvious solution for their improvement is in the construction of themselves. Especially in the improvement of their construction time which should be lower with usage of modular system than at classical layer system of the green roofs. This research also wants to speak about construction system for individual types of green roof. Where the purpose of this article is to set optimal solution for modular green roof panel which will be economical and environmentally friendly.

Abstract: Arcade, a regional architecture style in Taiwan, is gradually replaced by sidewalk with the prevailing global trends of architecture design, thereby bringing greater challenges to pedestrians comfort. Past researches suggest optimal urban wind regime can mitigate heat island effect and enhance pedestrians comfort level. Therefore, the relationship between arcade and pedestrian wind comfort as well as the influence of arcade’s height-to-width ratios (H/W) on urban wind environment are worth a thorough research. This study takes Farglory Kyoto Community as the example. Arcades in three varied sizes are compared: In Case 1, height-to-width ratio (H/W) =1.25; Case 2(H/W=1.54); Case 3(H/W=0.75). In Aug 2016, field measurement was conducted comparable anal++ysis on outdoor environmental comfort. The field measurement result indicates that, wind environment is more stable for arcade than sidewalk, and that air temperature of arcade is 3.9 °C lower than sidewalk, thereby concluding arcade tends to generate more pedestrian wind comfort in summer. The measurement result of Thermo GEAR G100EXD suggests, during the hottest time at noon, the difference between air temperature on sidewalk and on arcade reaches 8 °C. This study also proves that in subtropical climates, arcade is more likely to provide pedestrians with higher comfort level, and that air temperature on arcade is 3.9°C lower than outdoors. The lower the height-to-width ratio is, the more comfortable the environment appears to be.

Abstract: Emerging crises for resources and energy has became one of the major global issues. Unstoppable population and urban growth is demanding shelter. The figure for estimated housing shortage across the world according to the internationally recommended standards is 428,700,000 units. By the year 2030, an additional 3 billion people, about 40 percent of the world’s population, will need access to housing. This translates into a demand for 96,150 new affordable units every day and 4000 every hour.(United Nation –Habitate:2005)(128). All this unstoppable global population growth is resulting in high demand supply gap between resources and thus present trend concentrate to satisfy and minimize this gap. This shooting urbanization problem is leading towards diversion for easy and fast construction methodology.Along with this the problems associated to it are also increasing globally. The problem of Urban Heat Island and Urban Canyon Effect, CO2 emission , Green House Effect , Resource depletion and all such problems are demanding global attention to overcome it and make habitant sustainable for safeguarding future generations to come. The major hurdle for application of sustainable construction is barrier of human mind who concentrates more on initial cost of construction and negligence towards operations energy cost and pay back period calculations.The aim of the paper is to show feasibility of application of waste in construction elements like wall by analysing thermo resistive property of such waste filled cavity wall and equivalence cooling effect calculations for conventional clay brick wall , AC sheets , cavity wall and various waste filled cavity wall by making model and process of simulation using Ansys Fluent .The results of research work shows feasibility of adopting cavity wall and waste fill cavity wall for construction of wall because of its high thermoresistive property so as to mitigate global problems like Urban Heat Islands and operational energy consumption.

Abstract: In this chapter a critical analysis about natural materials to enhance energy performance and thermal comfort in indoor and outdoor spaces is dealt with. In particular, thermal insulation and passive cooling application in buildings are analyzed. The physical properties permitting to achieve these benefits are presented, as well as the method and the international standards to measure them. Benefits deriving from these materials’ employment as insulation layers or buildings envelope in general of, or in the case of urban paving, are described and then the single materials are illustrated.Experimental and numerical data, as reported in the bibliography, support the dissertation with examples from the most recent research contributions.

Abstract: As the climate warming up, the effects of the urban heat island have been an insurmountable issue in the urban development. In this paper, taking Tianjin for example, the research combined computer simulation with on-site measurement to evaluate the effects of different greening ratios on outdoor thermal environment. Besides, the accuracy of the simulation model has been verified by calibration. Research results determined that the increase of the greening ratio in the existing environment could improve the outdoor thermal environment in summer. But the limitations of green cooling was also pointed out, namely that the air temperature would infinitely close to a certain value with further increasing greening ratio.

Abstract: In this paper, data from 12 meteorological stations located throughout the greater metropolitan area of Thessaloniki - Greece are used for the calculation of location specific monthly Heating (HDD) and Cooling (CDD) Degree Days utilizing hourly records of the last three years. The HDD are calculated for base temperatures of 15 and 18°C and the CDD for base temperatures of 22 and 24°C by compacting average hourly data. The results show that the HDD average value of the various locations examined in Thessaloniki during the examined period (2010-2013), as compared to the corresponding value for the city center, is increased from 19% up to 48% (depending on the base temperature). The difference in the average value of CDD for the specified time period is more pronounced, as differences range from -10% to -40% compared to the corresponding value for the city center.

Abstract: Architectural typology and configurations on the urban wind environment are closely related, this research took the large-scaled high-density development in Taiwan of Fujhou Affordable Housing as a case study, the use of computer simulation Ecotect Analysis, for collection of air distribution to explore central courtyard buildings wind environment flow in the urban environment for congregate housing. This study according to simulation results tried to adjust the configuration program for a further amendment to meet pedestrians comfort. Results proved that the use of computer simulation for design review, could effectively achieve the most optimized design while also to reduce energy conservation and improve comfort, which will further as references for future architectural design and master planning.