scholarly journals Assessment of Outdoor Air Temperature with Different Shaded Area within an Urban University Campus in Hot-Humid Climate

2020 ◽  
Vol 12 (14) ◽  
pp. 5741 ◽  
Author(s):  
Sheikh Ahmad Zaki ◽  
Siti Wan Syahidah ◽  
Mohd Fairuz Shahidan ◽  
Mardiana Idayu Ahmad ◽  
Fitri Yakub ◽  
...  
Keyword(s):  
Air Temperature ◽  
Field Measurements ◽  
High Ratio ◽  
View Factor ◽  
University Campus ◽  
Outdoor Air ◽  
Humid Climate ◽  
Urban University ◽  
Hot Humid Climate

This study investigated the variation of outdoor air temperature in the shaded area covered by buildings in an urban university campus in Malaysia. In-situ field measurements were conducted to measure the distribution of outdoor air temperature at eight different locations for seven days. Meanwhile, the building-induced shadows were generated using the AutoCAD Revit software to investigate the air temperature change. The study used four urban morphological parameters namely building to greenery ratio, sky view factor (SVF), and height-to-street width (H/W) ratio. The relationship between building-induced shadow and outdoor air temperature (Tout) obtained from the in-situ measurement was investigated. The results showed that the building-induced shadows could lower air temperature. It can be noted that a high ratio of building to greenery resulted in a higher air temperature. In contrast, the area with a low SVF value due to the combination of prolonged shading by buildings and trees had a lower air temperature. Thus, the area with a high building ratio, low greenery ratio, higher SVF value, and low H/W ratio potentially has a higher outdoor air temperature. Conclusively, combination of building shading created by appropriate ratio of building morphology and sufficient greenery able to improve the microclimate of a campus area.

scholarly journals Effects of Urban Morphology on Microclimate Parameters in an Urban University Campus

2020 ◽  
Vol 12 (7) ◽  
pp. 2962 ◽  
Author(s):  
Sheikh Ahmad Zaki ◽  
Nurnida Elmira Othman ◽  
Siti Wan Syahidah ◽  
Fitri Yakub ◽  
Firdaus Muhammad-Sukki ◽  
...  
Keyword(s):  
Spatial Data ◽  
Urban Morphology ◽  
View Factor ◽  
Morphological Parameters ◽  
University Campus ◽  
Green Cover ◽  
Air Temperatures ◽  
Urban University ◽  
Cover Ratio

This study investigated the effects of urban morphology on microclimate parameters in an urban university campus in Malaysia. Outdoor air temperatures (Tout) were recorded at eight different locations inside the campus for seven days. The study used three urban morphological parameters such as green cover ratio, height-to-width (H/W) ratio, and sky view factor (SVF). The relationship between urban morphological parameters and Tout obtained from in situ measurements was investigated. The results showed that, at a dense green cover ratio of 22% in a 7833 m2 area where the H/W ratio was 0.2, Tout was reduced by about 1% due to a long building shadow cover (12 h) and a high range of SVF (from 0.61 to 0.68). The use of geographic information system (GIS) to generate the spatial data of Universiti Teknologi Malaysia Kuala Lumpur Campus (UTMKL), morphological features and in situ Tout distributions provided useful information of Tout variations, and proved the applicability of GIS as a useful tool in smart city urban planning.

scholarly journals Investigation on the Temperature Distribution of Asphalt Overlay on the Existing Cement Concrete Pavement in Hot-Humid Climate in Southern China

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Zuzhong Li ◽  
Yayun Zhang ◽  
Chunguang Fa ◽  
Xiaoming Zou ◽  
Haiwei Xie ◽  
...  
Keyword(s):  
Wind Speed ◽  
Relative Humidity ◽  
Solar Radiation ◽  
Prediction Model ◽  
Air Temperature ◽  
Concrete Pavement ◽  
Humid Climate ◽  
Temperature Prediction ◽  
Asphalt Overlay ◽  
Hot Humid Climate

Temperature is known to be one of the most important factors affecting the design and performance of asphalt concrete pavement. The distresses of asphalt overlay are closely related to its temperature, particularly in Guangxi, a hot-humid-climate region in China. This research is to analyze the impact of meteorological factors on temperature at 2 cm depth in asphalt overlay by ReliefF algorithm and also obtain the temperature prediction model using MATLAB. Two test sites were installed to monitor the temperatures at different pavement depths from 2014 to 2016; meanwhile, the meteorological data (including air temperature, solar radiation, wind speed, and relative humidity) were collected from the two meteorological stations. It has been found that the temperature at 2 cm depth experiences greater temperature variation, and the maximum and minimum temperatures of asphalt overlay, respectively, occur at 2 cm depth and on the surface. Besides, the results of ReliefF algorithm have also shown that the temperature at 2 cm depth is affected significantly by solar radiation, air temperature, wind speed, and the relative humidity. Based on these analyses, the prediction model of maximum temperature at 2 cm depth is developed using statistical regression. Moreover, the data collected in 2017 are used to validate the accuracy of the model. Compared with the existing models, the developed model was confirmed to be more effective for temperature prediction in hot-humid region. In addition, the analysis of rutting depth and overlay deformation for the two test sections with different materials is done, and the results have shown that reasonable structure and materials of asphalt overlay are vital to promote the high-temperature antideforming capability of pavement.

scholarly journals Indoor Thermal Performance of Ventilated Dwellings Using Fly Screens in the Hot-Humid Climate of Chennai, India

2009 ◽  
Vol 4 (2) ◽  
pp. 150-157 ◽  
Author(s):  
Vijayalaxmi J ◽  
S.P Sekar
Keyword(s):  
Solar Radiation ◽  
Air Temperature ◽  
Thermal Performance ◽  
Indoor Air ◽  
Tropical Climate ◽  
Summer Period ◽  
Humid Climate ◽  
Floor Area ◽  
Hot Humid Climate ◽  
Heating Up

In a hot-humid tropical climate, indoor thermal performance can be enhanced by comfort ventilation. Indoor ventilation depends upon building opening size. But risks involved in providing openings include ingress of mosquitoes and insects which thrive in the tropical climate. A practical and prevalent option to prevent insects in ventilated dwellings of the tropical, hot-humid city of Chennai, India is through the use of fly screens. Fly screens, when used over openings, prevent a certain quantum of solar radiation and wind from entering inside the rooms. Reduced direct solar radiation prevents the indoors from heating up, while reduced wind movement prevents the cross ventilation. Therefore, it is important to know the indoor thermal performance of ventilated rooms in the presence of fly screens with changing opening sizes. The criterion to evaluate indoor thermal performance in this paper is indoor air temperature. The aim of this research is to investigate the influence of fly screens on openings with varying sizes, in a naturally ventilated dwelling in the hot-humid climate of Chennai, India, during the summer period. The results of the study show that fly screens raise the indoor air temperature when openings are in the range of 100% to 35% of the room floor area. There is no significant change in the indoor air temperature when the opening sizes are less than 30% of the room floor area.

scholarly journals Mid-afternoon Outdoor Biometeorological Conditions in a Hot-humid Climate of Minna in Nigeria, West Africa during the Year 2012

2021 ◽  
pp. 52-62
Author(s):  
Christian A. Njoku ◽  
Ikenna Orisakwe ◽  
Vincent N. Ojeh
Keyword(s):  
Correlation Coefficient ◽  
Air Temperature ◽  
Humid Climate ◽  
North Central ◽  
The Difference ◽  
Definition Of ◽  
Reference Environment ◽  
Hot Humid Climate ◽  
The City ◽  
Rayman Model

The human biometeorological conditions at mid-afternoon during 12 months of 2012 in the city of Minna North-Central Nigeria have been evaluated based on energy budget indices (UTCI and PET) using climate parameters -air temperature, relative humidity, wind speed and solar radiation) observed at 15:00LST as input into the Rayman model. Air temperature demonstrated strongest significant correlation coefficient (r) with UTCI and PET (r= 0.91, r= 0.93) (P<0.0001) while windspeed show weakest association with them(r=-0.10, r=-0.20) (P<0.03, P<0.001) respectively. March and August were characterized by peak and slightest monthly thermal stress conditions according to both indices. The correlation coefficient between both indices was significantly (P<0.0001) very strong (r=0.98) and more noticeable for equivalent temperatures in strong stress thresholds (UTCI>=32°C, PET>=35°C), which shows that both indices can be used indifferently in warm climates. However, during May to October, UTCI better expressed warm conditions than PET mainly due to the difference in the definition of reference environment for both indices; this study is relevant to the urban sightseeing industry as tourists would most likely opt for a period of lesser thermal discomfort.

scholarly journals Retrofitting solutions for a campus building to mitigate urban heat island in a hot humid climate

2021 ◽  
Vol 2042 (1) ◽  
pp. 012062
Author(s):  
Vajreshwari Patil ◽  
Maite Bizcarguenaga ◽  
Katherine Lieberknecht ◽  
Juliana Felkner
Keyword(s):  
Surface Temperature ◽  
Urban Heat Island ◽  
Air Temperature ◽  
Ambient Air ◽  
Cooling Effect ◽  
Heat Island ◽  
Humid Climate ◽  
Temperature Reduction ◽  
Urban Heat ◽  
Hot Humid Climate

Abstract In this study we examine the summer cooling effects of trees and green facades on reducing urban heat island effects. Using ENVI-met model simulations, we investigate the influence of added greenery on the surface and ambient air temperature and its role on air fluctuations in the hot humid climate of Austin, TX, at pedestrian height. Under the specific conditions considered in this model, the results show the combination of trees and green facades has a greater cooling effect. Added greenery to the building mostly impacts the building's surface temperature during the hottest hours of the day, registering a maximum surface temperature reduction of 20.33°C. Simulations also show a maximum overall potential air temperature reduction of 0.54°C, and a maximum potential air temperature cooling effect near the building of 0.91°C. Future research should be conducted to address this study's limitations. Nevertheless, these findings can provide architects, designers, planners, and policymakers with a better understanding of the many benefits trees and green facades have, and provide them with the necessary tools to implement new solutions across sectors and scales to reduce the impacts urban areas have on the environment and provide a better living for all.

scholarly journals Influence of Courtyard Ventilation on Thermal Performance of Office Building in Hot-Humid Climate: A Case Study

2018 ◽  
Vol 34 ◽  
pp. 02053
Author(s):  
Esra’a Sh. Abbaas ◽  
Ala’eddin A. Saif ◽  
MAC Munaaim ◽  
Md. Azree Othuman Mydin
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Thermal Performance ◽  
Natural Ventilation ◽  
Office Building ◽  
Humid Climate ◽  
Airborne Pollutants ◽  
Indoor Sources ◽  
Hot Humid Climate

The influence of courtyard on the thermal performance of Development Department office building in University Malaysia Perlis (UniMAP, Pauh Putra campus) is investigated through simulation study for the effect of ventilation on indoor air temperature and relative humidity of the building. The study is carried out using EnergyPlus simulator interface within OpenStudio and SketchUp plug in software to measure both of air temperature and relative humidity hourly on 21 April 2017 as a design day. The results show that the ventilation through the windows facing the courtyard has sufficient effect on reducing the air temperature compared to the ventilation through external windows since natural ventilation is highly effective on driving the indoor warm air out to courtyard. In addition, the relative humidity is reduced due to ventilation since the courtyard has high ability to remove or dilute indoor airborne pollutants coming from indoor sources. This indicates that the presence of courtyard is highly influential on thermal performance of the building.

Influence of Water Bodies on Outdoor Air Temperature in Hot and Humid Climate

ICSDC 2011 ◽  
2012 ◽  
Author(s):  
Nyuk Hien Wong ◽  
Chun Liang Tan ◽  
Andrita Dyah Shinta Nindyani ◽  
Steve Kardinal Jusuf ◽  
Erna Tan
Keyword(s):  
Air Temperature ◽  
Water Bodies ◽  
Outdoor Air ◽  
Humid Climate ◽  
Influence Of Water ◽  
Hot And Humid Climate

scholarly journals Thermal Performance of Vertical Courtyard System in Office Buildings Under Typical Hot Days in Hot-Humid Climate Area: A Case Study

2020 ◽  
Vol 12 (7) ◽  
pp. 2591
Author(s):  
Jin Wei ◽  
Fangsi Yu ◽  
Haixiu Liang ◽  
Maohui Luo
Keyword(s):  
Air Temperature ◽  
Thermal Performance ◽  
Weather Conditions ◽  
Office Buildings ◽  
Radiation Environment ◽  
Humid Climate ◽  
Hot Days ◽  
Cooling Effects ◽  
Hot Humid Climate

Due to the different types of courtyards in vertical courtyard system (VCS), their impacts on thermal performance in office buildings may vary. To better understand this issue, this paper investigates the thermal performance impact of three typical vertical courtyards. A field case study was conducted in VCSs during two typical extreme hot days under hot-humid climate conditions. The results show that the vertical courtyards have significant cooling effects under hot-humid climatic conditions. Via testing on linear, integrated, and rooftop courtyard with fusion layout, the fusion one has an obviously positive impact on air temperature reduction (4.3 °C). Compared with the linear and integrated courtyards, the maximum air temperature difference of fusion layout is around 1.6 °C. The thermal radiation environment of the fusion layout was better than that of the other two (linear and integrated). Besides, the surface temperature of the pavements (wood panel) in the vertical courtyards can reach 47 °C, while the vegetation can lower it by 8 °C under the same weather conditions. These findings show that the courtyard with fusion layout is more suitable for extreme hot weather conditions.

scholarly journals Study on the Effect of Streets’ Space Forms on Campus Microclimate in the Severe Cold Region of China—Case Study of a University Campus in Daqing City

2020 ◽  
Vol 17 (22) ◽  
pp. 8389
Author(s):  
Hong Jin ◽  
Liang Qiao ◽  
Peng Cui
Keyword(s):  
Wind Speed ◽  
Air Temperature ◽  
Urban Areas ◽  
Thermal Environment ◽  
Heat Convection ◽  
Heat Radiation ◽  
View Factor ◽  
University Campus ◽  
Human Comfort ◽  
Open Type

In urban areas, local microclimate is influenced by architectural forms, which will in turn affect human comfort. Taking Daqing as an example, this article studies the microclimate of a university campus in the severe cold area in China. Based on the space features of the streets, we categorize the streets into three types: open type, semi-open type, and street-entry type. Through analysis, this article researches microclimates of the three kinds of streets, the influence of building heating on the surrounding thermal environment, the relationship between streets’ morphology features and microclimate and human comfort (physiological equivalent temperature, PET). By study and analysis, we have the following findings: for open-type streets, the average globe temperatures of streets with different orientations can reach 1.3 °C in winter because of the influence of sidewalk trees. For semi-open-type streets, streets temperature is under the influence of the locating directions of buildings. The maximum air temperature difference among streets with different building arrangements reaches 2.1 °C in winter. For street-entry-type streets, the height–width ratios and orientations of streets are related to the continuity degree of the street interfaces. The building interface acts as a heating element and affect the surrounding thermal environment by heat convection and heat radiation. Analysis demonstrates that heat convection has a more obvious effect on rising surrounding temperature than heat radiation. Buildings with higher heat radiation witness higher globe temperature. For street-entry-type streets and semi-open-type streets, the SVF (sky view factor) and L/C (plane opening rate) of streets are negatively correlated with temperature and PET, but positively correlated with wind speed. If the SVF increases 0.1, the air temperature will reduce 0.1 °C, the wind speed will increase 0.19 m/s, and the PET will reduce 0.7 °C.

scholarly journals An Assessment of the Spatial Comfort at the Open Piazza of Baiturrahman Mosque, Banda Aceh, Indonesia

2020 ◽  
Vol 9 (2) ◽  
pp. 50-62
Author(s):  
Laina Hilma Sari ◽  
Izziah Hasan ◽  
Erna Meutia
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Sensation ◽  
Field Measurements ◽  
Outdoor Thermal Comfort ◽  
Visual Comfort ◽  
Outdoor Air ◽  
White Marble ◽  
The Tropics ◽  
Banda Aceh

 The Baiturrahman Grand Mosque is well-known as the identity of Banda Aceh town, Indonesia. The extensive renovation was carried out in 2015 to the Mosque, presenting an open piazza coated with glossy white marble replacing the previous greeneries and grass. This change creates a much different thermal sensation of the prior environment. This condition also invites the contrast to respond and define spatial comfort, including thermal and visual comfort. Therefore, this study conducts an assessment of thermal and visual comfort at the open piazza, which was done through field measurements. The outdoor thermal comfort was calculated using the equations proposed by Sangkertadi that are appropriate for the tropics. The visual comfort was examined using the De Boer glare scale. The result shows the discomfort appearance for both thermal and visual comfort. The study gives recommendations, such as planting greeneries, providing more shades for achieving lower outdoor air temperature. Replacing the glossy marble with the diffusing and rough surface will reduce the glare for getting the more acceptable visual comfort against the marbles.

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