scholarly journals Development of a Distributed Modeling Framework to Estimate Thermal Comfort along 2020 Tokyo Olympic Marathon Course

Atmosphere ◽  
2018 ◽  
Vol 9 (6) ◽  
pp. 210 ◽  
Author(s):  
Satoshi Hirabayashi ◽  
Tsutomu Abe ◽  
Fumiko Imamura ◽  
Chie Morioka
Keyword(s):  
Solar Radiation ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Energy Budget ◽  
View Factor ◽  
Street Trees ◽  
M Cell ◽  
Modeling Framework ◽  
Distributed Modeling ◽  
Human Thermal Comfort

Heat stress is an issue for marathon races in the summer, such as the one planned for the 2020 Tokyo Summer Olympic games. The Tokyo Metropolitan Government is planning to grow existing street trees’ canopies to enlarge their shade to reduce air temperature and solar radiation. To formulate a baseline to assess the effect of street trees and buildings on human thermal comfort, Distributed-COMfort FormulA (D-COMFA), a prototype of a distributed computer model using a geographic information system (GIS) was developed. D-COMFA calculates the energy budget of a human body on a 1 m cell basis, using readily available datasets such as weather measurements and polygon data for street structures. D-COMFA was applied to a street segment along the marathon course in Tokyo on an hourly-basis on 9 August 2016, the hottest day in Tokyo in 2016. Our case study showed that the energy budget was positively related to the sky view factor, air temperature, and solar radiation. The energy budget was reduced on average by 26–62% in the shade throughout the day.

scholarly journals Field Assessment of Neighboring Building and Tree Shading Effects on the 3D Radiant Environment and Human Thermal Comfort in Summer within Urban Settlements in Northeast China

2020 ◽  
Vol 2020 ◽  
pp. 1-19
Author(s):  
Jing Du ◽  
Lin Liu ◽  
Xin Chen ◽  
Jing Liu
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Short Wave ◽  
Radiant Flux ◽  
View Factor ◽  
Mean Radiant Temperature ◽  
Human Thermal Comfort ◽  
Long Wave ◽  
Shading Effects ◽  
Radiant Temperature

Shading is one of the most effective strategies to mitigate urban local-scale heat stress during summer. Therefore, this study investigates the effects of shading caused by buildings and trees via exhaustive field measurement research on urban outdoor 3D radiant environment and human thermal comfort. We analyzed the characteristics of micrometeorology and human thermal comfort at shaded areas, and compared the difference between building and tree shading effects as well as that between shaded and sunlit sites. The results demonstrate that mean radiant temperature Tmrt (mean reduction values of 28.1°C for tree shading and 28.8°C for building shading) decreased considerably more than air temperature Ta (mean reduction values of 1.9°C for tree shading and 1.2°C for building shading) owing to shading; furthermore, the reduction effect of shading on UTCI synthesized the variation in the above two parameters. Within the shaded areas, short-wave radiant components (mean standardized values of 0.104 for tree shading and 0.087 for building shading) decreased considerably more than long-wave radiant components (mean standardized values of 0.848 for tree shading and 0.851 for building shading) owing to shading; the proportion of long-wave radiant flux densities absorbed by the reference standing person was high, leading to a relatively high long-wave mean radiant temperature, and R2 between long-wave mean radiant temperature and air temperature exceeded 0.8. Moreover, the directional sky view factor (SVF) was utilized in this study, and it showed significant positive correlation with short-wave radiant flux densities, but no statistically evident correlation with long-wave radiant flux densities. Meanwhile, Tmrt was most relevant with SVFS⟶ with R2 of 0.9756. Furthermore, UTCI rose two categories at the sunlit areas compared with that at the shaded areas. In contrast, Ta and Tmrt played the first positive role in UTCI at shaded and sunlit areas, respectively.

scholarly journals Summer Outdoor Thermal Comfort in Urban Commercial Pedestrian Streets in Severe Cold Regions of China

2020 ◽  
Vol 12 (5) ◽  
pp. 1876 ◽  
Author(s):  
Zheng Zhu ◽  
Jing Liang ◽  
Cheng Sun ◽  
Yunsong Han
Keyword(s):  
Solar Radiation ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Sensation ◽  
Psychological Adaptation ◽  
Outdoor Environment ◽  
Outdoor Thermal Comfort ◽  
Climate Index ◽  
View Factor ◽  
Cold Regions

This paper investigates outdoor thermal comfort in summer in commercial pedestrian streets in Harbin, using meteorological measurements and questionnaire surveys (1013 valid questionnaires). The results demonstrate that: (1) Thermal sensation has a lower range in an outdoor environment with smaller sky view factor (SVF) and less fluctuation, while the thermal sensation vote (TSV) range is more dispersed in an outdoor environment with larger SVF and more fluctuation; (2) In the urban, high-density commercial districts in Harbin, the air temperature and solar radiation have a greater influence on outdoor thermal sensation, while wind speed has less of an influence, and residents in areas with less fluctuations are more sensitive to air temperature and solar radiation; (3) The universal thermal climate index (UTCI) can accurately evaluate outdoor thermal comfort in Harbin in summer, with a neutral UTCI value of 19.3 °C and a range from 15.6 to 23.0 °C; (4) The actual acceptable thermal range is 16.8–29.3 °C, and this takes into account the psychological adaptation of the residents, which provides a more practical reference value; (5) With reference to the psychological adaptation, the outdoor thermal sensation of residents in early summer is about 0.5 TSV higher than that in late summer. These results provide a theoretical basis and a technical reference for the design of commercial pedestrian streets in severe cold regions.

scholarly journals Human Thermal Comfort Situation in the Goller (Lakes) District of Turkey

2016 ◽  
pp. 137-144
Author(s):  
Yuksel Guclu
Keyword(s):  
Relative Humidity ◽  
Thermal Comfort ◽  
Human Health ◽  
Air Temperature ◽  
Mediterranean Region ◽  
Human Thermal Comfort ◽  
Almost All ◽  
Relative Humidity Data ◽  
Recreation Activities

Abstract In this study, the determination of the human thermal comfort situation in the Goller District (in the Mediterranean Region) of Turkey has been aimed. In the direction of the aim, the air temperature and relative humidity data of total 11 meteorology stations have been examined according to The Thermo-hygrometric Index (THI) and the New Summer Simmer Index (SSI). According to this, it has been determined that the thermal comfort conditions are not appropriate in the period of October-May on average monthly. The months of June and September are the most appropriate to almost all kinds of tourism and recreation activities in the outdoor in terms of thermal comfort. When THI and SSI indices’ values are evaluated together, the periods between 5th – 25th June and 29th August-16th September are the most appropriate periods in the study area on average in terms of the thermal comfort for the tourism and recreation activities in the outdoor. Keywords: Thermal comfort, human health, The Thermo-Hygrometric Index, The Summer Simmer Index, Goller District, Turkey.

scholarly journals A Study of the Thermal Environment and Air Quality in Hot–Humid Regions during Running Events in Southern Taiwan

Atmosphere ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1101
Author(s):  
Si-Yu Yu ◽  
Andreas Matzarakis ◽  
Tzu-Ping Lin
Keyword(s):  
Air Quality ◽  
Solar Radiation ◽  
Thermal Comfort ◽  
Real Time ◽  
Thermal Environment ◽  
Monitoring Data ◽  
Integrated Analysis ◽  
View Factor ◽  
Thermal Discomfort ◽  
Southern Taiwan

It is quite difficult to investigate thermal comfort in hot–humid regions, and there have not been many real case studies or research related to this issue. In this article, four running events held in nearby popular travel spots in Kaohsiung, the largest city in southern Taiwan, were selected to analyze the influence of thermal environment and air quality on thermal comfort. Mostly real time environmental monitoring data were applied for estimating thermal indicators, along with Sky View Factor (SVF) data taken at the sites of the running scheduled routes, to analyze the thermal performance of participants at running events. Compared with runners, walkers (local residents, fans, and staff of the events) would be exposed to a greater risk of thermal discomfort with increasing time spent on the routes. With the integrated analysis, mPET (modified physiologically equivalent temperature) can be viewed as a relatively comprehensive indicator in considering both environmental thermal conditions and the biometrical differences of activities and clothing types. From the results, a good correlation between mPET and solar radiation/SVF was obtained, which indicated that mPET could be sufficiently sensible in revealing the thermal condition variation from one site to another during the route with time. Based on the discomfort risk assessment, for runners, the event held in autumn with lower SVF at the route sites would be less risky of thermal discomfort, while the event held in spring with lower solar radiation would be more comfortable for walkers. As for air quality condition, the inappropriateness of holding winter outdoor activities in Kaohsiung was obviously shown in both real time monitoring data and long term analysis.

scholarly journals Experimental study on dynamic thermal environment of passenger compartment based on thermal evaluation indexes

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042094299
Author(s):  
Liang Zhang ◽  
Liangkui Qi ◽  
Jianhua Liu ◽  
Qingqing Wu
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Prediction Accuracy ◽  
Thermal Environment ◽  
Temperature Model ◽  
Equivalent Temperature ◽  
Vote Model ◽  
Evaluation Indexes ◽  
Human Thermal Comfort ◽  
Experimental Values

In this article, the thermal environment and the human thermal comfort of car cabin under different driving states in summer were studied experimentally. The weighted predictive mean vote model and the weighted equivalent temperature model were used for calculation and compared with the experimental values. The experimental results show that the air temperature and relative humidity distribution in cabin are affected by the space position and driving state. The temperature of the cabin seat, which is affected by solar radiation and crew, in the heating stage is slightly higher than the air temperature, while the cooling rate in the cooling stage is much lower than the air temperature. The predictive mean vote model and the equivalent temperature model are basically consistent with the actual thermal comfort of human body under the idle and driving conditions with the change of time. The prediction accuracy of the two models under the idle condition is higher than that under the driving condition, and the overall prediction accuracy of the equivalent temperature model is higher than that of the predictive mean vote model.

scholarly journals Investigation on Airport Landscape Cooling Associated with Irrigation: A Case Study of Adelaide Airport, Australia

2020 ◽  
Vol 12 (19) ◽  
pp. 8123
Author(s):  
Jingming Qian ◽  
Shujiang Miao ◽  
Nigel Tapper ◽  
Jianguang Xie ◽  
Greg Ingleton
Keyword(s):  
Global Warming ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Trial Period ◽  
Land Utilization ◽  
Irrigation Area ◽  
Human Thermal Comfort ◽  
Loading And Unloading ◽  
Maximum Air Temperature

Extreme summertime heat is becoming a major issue for aircraft operations. As global temperatures continue to rise, some of the heaviest planes on the longest flights may eventually be unable to depart during the hottest part of summer days. During summer days, some airports have to reduce the payload of aircraft, including cargo and/or passengers in the hotter days of summer. Nonetheless, there is no existing body of research on the potential for airport cooling. Furthermore, extreme heat on the ground also affects airport workers; loading and unloading luggage and servicing platforms between flights could become more arduous. With global warming proceeding, it is becoming increasingly urgent to find a suitable strategy to cool airport environments, perhaps by irrigation of a vegetated landscape. All airports have large enclosed areas (usually of grass) acting as a buffer between airport activities and the adjacent industrial, commercial and residential land utilization. This paper describes the trial of irrigating the buffer area of Adelaide airport and analyzes the performance of irrigation cooling for Adelaide airport, examining whether this can benefit human thermal comfort. Results indicate that irrigation provides cooling, and the cooling effect reduces along with the increasing instance from the middle of the irrigation area. At 15:00, the average air temperature was 1.8 °C cooler in the middle of the irrigation area than in the non-irrigation area, and the relative humidity was 5.8% higher during the trial period. On an extremely hot day (the maximum air temperature was 45.4 °C), it was 1.5 °C cooler in the middle of the irrigation area than upwind the of irrigation area, and 0.8 °C cooler than downwind of the irrigation area at 13:00. Human thermal comfort (HTC) is unfavorable in the runway, but greater improvements can be made through promotion of irrigation.

Effect of solar radiation on human thermal comfort in a tropical climate

2020 ◽  
pp. 1420326X1989176 ◽  
Author(s):  
Somsak Chaiyapinunt ◽  
Nopparat Khamporn
Keyword(s):  
Solar Radiation ◽  
Surface Temperature ◽  
Thermal Comfort ◽  
Human Body ◽  
Glass Surface ◽  
Tropical Climate ◽  
Direct Solar Radiation ◽  
Diffuse Solar Radiation ◽  
Human Thermal Comfort ◽  
Comfort Condition

The contribution of solar radiation on the global thermal comfort and local thermal comfort condition for a person sitting near a glass window in a building located in a tropical climate was studied. The effects of transmitted direct solar radiation, transmitted diffuse solar radiation, inside glass surface temperature and distance of a seated person from the glass window on the predicted percentage of dissatisfied (PPD) and plane radiant temperature asymmetry (RTA) were studied. PPD and RTA due to transmitted diffuse solar radiation and high inside glass surface temperature were decreased with the distance from the glass window. PPD was decreased exponentially with the distance from the glass window, while RTA was decreased slowly with the distance from the glass window. The findings show that PPD and RTA due to transmitted direct solar radiation striking the human body are not dependent on the distance from the glass window, but they are dependent on the magnitude and direction of the solar beam radiation incident on a human body. The results of the study would help the building designers to be able to design the interior working space for the tenant sitting near the glass window to achieve the acceptable level of thermal comfort condition.

Temperature and human thermal comfort effects of street trees across three contrasting street canyon environments

2015 ◽  
Vol 124 (1-2) ◽  
pp. 55-68 ◽  
Author(s):  
Andrew M. Coutts ◽  
Emma C. White ◽  
Nigel J. Tapper ◽  
Jason Beringer ◽  
Stephen J. Livesley
Keyword(s):  
Thermal Comfort ◽  
Street Canyon ◽  
Street Trees ◽  
Human Thermal Comfort

scholarly journals ANÁLISE DO CONFORTO TÉRMICO HUMANO NO MUNICÍPIO DE ARAPIRACA – ALAGOAS, UTILIZANDO SOFTWARE MATLAB (ANALYSIS OF THE HUMAN THERMAL COMFORT THE CITY OF ARAPIRACA - ALAGOAS USING SOFTWARE MATLAB)

2015 ◽  
Vol 7 (5) ◽  
pp. 939
Author(s):  
Juliete Baraúna dos Santos
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Effective Temperature ◽  
Rainy Season ◽  
Prolonged Exposure ◽  
Urban Climate ◽  
Heat Stroke ◽  
Human Thermal Comfort ◽  
Discomfort Index ◽  
The City

Foram obtidas medidas das variáveis meteorológicas temperatura do ar, umidade relativa do ar e velocidade do vento através da estação automática instalada em Arapiraca com a finalidade de monitorar as condições de tempo no município em diferentes períodos (época chuvosa e seca). Sendo utilizado o índice de desconforto (ID), o índice de desconforto de Kawamura (IDK), índice da temperatura efetiva (TE) e o índice de temperatura efetiva em função do vento (TEV). Os valores mais elevados dos índices que foram registrados para o período chuvoso, foram do índice id com aproximadamente 2,5 °C acima dos valores observados da temperatura do ar (em média 26,5 °C), caracterizando crescente desconforto para os indivíduos locais.  Para o período seco não houve registros de grandes variações entre os respectivos índices. E assim como no período chuvoso, os valores mais elevados no período seco foram do índice id, indicando nesse período também forte desconforto. Os valores obtidos estiveram condizentes com a literatura, sendo a sensação térmica mais preponderante durante o inverno. E, de acordo com as variações, em todo período de estudo (05 de maio de 2008 a 05 de maio de 2011) a população foi submetida aos alertas de atenção e muito cuidado, situação esta que pôde provocar fadiga ou cãibras, esgotamento e insolação nos casos de exposição prolongada e atividade física.      A B S T R A C T Measurements of meteorological variables air temperature, relative humidity and wind speed by automatic station installed in Arapiraca in order to monitor the weather conditions in the city in different periods (dry and rainy season) were obtained. Being used the discomfort index (ID), the discomfort index of Kawamura (IDK), index of effective temperature (TE) and the index of effective temperature as a function of wind (TEv). Higher index values ​​that were recorded for the rainy season, the index id were approximately 2.5 ° C above the observed values ​​of air temperature (average 26.5 ° C), indicating increasing discomfort for local individuals . For the dry period there were no reports of large variations between the respective indices. And just as the rainy season, the highest values ​​in the dry season were the index id, indicating that period also strong discomfort. The values ​​obtained were consistent with the literature, the most predominant wind chill during the winter. And, according to the variations in the study period (May 5, 2008 to 05 maio 2011) the population was subjected to warnings of attention and care, a situation that could cause fatigue or cramps, exhaustion and heat stroke in cases of prolonged exposure and physical activity.   Key-Words: Urban climate. Thermal comfort Human. Bioclimatic

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