Application of thermal comfort assessment models to indoor areas near glazed walls – experimental evaluation

In this paper, some of the results of an experimental study are presented. Its purpose was to better understand the impact of glazing on thermal comfort of users of indoor spaces (living and working), especially in the areas near glazed walls. Glazed elements, such as windows and glazed doors, allow visual access to the outdoor environment and the entrance of natural light and solar heat gains but they are often the cause of unwanted heat losses and gains and are disturbing elements in obtaining thermal comfort, both in global terms and in what concerns local discomfort due to radiant asymmetries and/or air draughts. Furthermore, solar radiation directly affecting users in the vicinity of glazing can also cause discomfort. These disturbances are recognized by users, both on cold winter days and on hot summer days. To assess thermal comfort or thermal neutrality of a person in a particular indoor space, it is important to know their location within that space. Thus, in order to adequately assess thermal comfort in the areas near the glazing, the indoor thermal environment must be characterized for this specific location. In this study, two indoor spaces (a classroom and an office-room) of a school building were monitored at different periods of the year. The measurements of the environmental parameters were performed both in the center of the rooms and in the areas near the glazing. Five models of thermal comfort assessment were then applied to the results, in order to compare the comfort conditions between the two studied locations and to evaluate the applicability of these models to the areas close to glazed walls. It was observed there was clearly a greater variability of comfort conditions in the vicinity of the glazed walls when compared to the center of the rooms. The application of thermal comfort assessment models to the two studied rooms was able to reveal the differences between the two compared locations within each space. It was also possible to show the effect of incoming solar radiation and the influence of the geometry of the spaces and of the ratio between glazed area and floor area by comparing the results for both spaces. The assessment model proposed by LNEC (Portuguese National Laboratory of Civil Engineering) proved to be the most adapted to Portuguese users’ habits.

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Impact of solar reflectance of wall and road on outdoor thermal comfort - experimental study in a street canyon setup

MATEC Web of Conferences ◽

10.1051/matecconf/201928202010 ◽

2019 ◽

Vol 282 ◽

pp. 02010

Author(s):

Kiran Kumar D E V S ◽

Man Pun Wan ◽

Mandi Zhou ◽

Yongping Long ◽

Bing Feng Ng

Keyword(s):

Solar Radiation ◽

Thermal Comfort ◽

Street Canyon ◽

Thermal Environment ◽

Longwave Radiation ◽

Environmental Parameters ◽

Outdoor Thermal Comfort ◽

Width Ratio ◽

Diffuse Solar Radiation ◽

Solar Reflectance

Thermal environment in an urban street canyon is primarily affected by prevailing air conditions, wind flow, solar radiation as well as thermal properties of the surrounding urban structures and pavement surfaces that affect the reflection, absorption and re-emission of solar radiation. Experiments were conducted in a 1:5 scale test setup consisting of North-South oriented street canyon (height to width ratio 1.7) located in Singapore. Test cases covering two levels solar reflectance of walls (0.35 and 0.57) and road (0.12 and 0.55) were conducted in a three-month period. Environmental parameters including direct beam and diffuse solar radiation, net radiation (incoming and outgoing shortwave and longwave radiation) and wind speed were continuously measured at the top of the canyon. Thermal comfort parameters including air temperature, relative humidity, air velocity and globe temperature were also monitored continuously inside the street canyon. When the solar reflectance of canyon surfaces increases, mean radiant temperature (MRT) reduces by up to 1.2°C during daytime and 2.5°C during the night. Such reduction leads to reduced occurrence of heat stress by 34% and 42% during the day and night times, respectively, as measured by the universal thermal comfort index (UTCI). This paper further discusses the effect of longwave radiation on MRT in the street canyon due to changes in canyon solar reflectance.

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Numerical Investigation of the Influence of Vegetation on the Aero-Thermal Performance of Buildings with Courtyards in Hot Climates

Energies ◽

10.3390/en14175388 ◽

2021 ◽

Vol 14 (17) ◽

pp. 5388

Author(s):

Hao Sun ◽

Carlos Jimenez-Bescos ◽

Murtaza Mohammadi ◽

Fangliang Zhong ◽

John Kaiser Calautit

Keyword(s):

Thermal Comfort ◽

Thermal Performance ◽

Natural Ventilation ◽

Spatial Configuration ◽

Environmental Parameters ◽

Comfort Levels ◽

Indoor Comfort ◽

The Impact ◽

Indoor Spaces ◽

Good Agreement

Natural ventilation is an energy-efficient way to provide fresh air and enhance indoor comfort levels. The wind-driven natural ventilation in courtyards has been investigated by many researchers, particularly the influence of the spatial configuration and environmental parameters on the ventilation and thermal comfort performance. However, previous research has mainly focused on the courtyard region instead of the indoor spaces surrounding it. Additionally, as a microclimate regulator, courtyards are rarely assessed in terms of the impact of vegetation, including its impact on energy consumption and thermal comfort. Evapotranspiration from vegetation can help lower air temperature in the surrounding environment and, therefore, its influence on the ventilation and thermal comfort in buildings with courtyards should be evaluated. The present study investigates the impact of vegetation on the aero-thermal comfort conditions in a courtyard and surrounding buildings in hot climates. Computational fluid dynamics was employed to evaluate the aero-thermal comfort conditions of the courtyard and surrounding buildings with different configurations of vegetation. The modeling was validated using previous works’ experimental data, and good agreement was observed. Thermal comfort indices were used to assess thermal performance. The study also evaluated the cover, height and planting area of vegetation in the courtyard. The results of this study can help develop tools that can assist the addition of vegetation in courtyards to maximize their effects. Future works will focus on looking at the influence of the strategies on different designs and layouts of courtyards.

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Evaluating the Impact of Solar Radiation on Outdoor Thermal Comfort by the Development and Validation of a Simple Urban Climatic Model

Solar Energy ◽

10.1115/isec2006-99012 ◽

2006 ◽

Cited By ~ 1

Author(s):

Yuemei Zhu ◽

Jing Liu ◽

Yang Yao ◽

Zuiliang Ma ◽

Aya Hagishima ◽

...

Keyword(s):

Solar Radiation ◽

Thermal Comfort ◽

Air Temperature ◽

Thermal Environment ◽

Thermal Conditions ◽

Outdoor Thermal Comfort ◽

Outdoor Thermal Environment ◽

Development And Validation ◽

The Impact ◽

Canopy Model

In this paper, in order to predict the outdoor thermal environment, a simple multi-layer canopy model coupled with calculation of outdoor thermal comfort was developed. SET* value was used to estimate the pedestrian level of thermal comfort in the outdoor thermal environment. Preliminary verification of this model using observational data on the outdoor thermal conditions showed good results. In addition, the results show that outdoor thermal comfort is significantly different with air temperature. Except for air temperature, both solar radiation and humidity play important roles on outdoor thermal comfort.

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How Can We Adapt Thermal Comfort for Disabled Patients? A Case Study of French Healthcare Buildings in Summer

Energies ◽

10.3390/en14154530 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4530

Author(s):

Youcef Bouzidi ◽

Zoubayre El Akili ◽

Antoine Gademer ◽

Nacef Tazi ◽

Adil Chahboun

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Residential Buildings ◽

Linear Regression Analysis ◽

Environmental Parameters ◽

Physical Parameters ◽

Mean Radiant Temperature ◽

Operative Temperature ◽

Neutral Temperature ◽

Radiant Temperature

This paper investigates adaptive thermal comfort during summer in medical residences that are located in the French city of Troyes and managed by the Association of Parents of Disabled Children (APEI). Thermal comfort in these buildings is evaluated using subjective measurements and objective physical parameters. The thermal sensations of respondents were determined by questionnaires, while thermal comfort was estimated using the predicted mean vote (PMV) model. Indoor environmental parameters (relative humidity, mean radiant temperature, air temperature, and air velocity) were measured using a thermal environment sensor during the summer period in July and August 2018. A good correlation was found between operative temperature, mean radiant temperature, and PMV. The neutral temperature was determined by linear regression analysis of the operative temperature and Fanger’s PMV model. The obtained neutral temperature is 23.7 °C. Based on the datasets and questionnaires, the adaptive coefficient α representing patients’ capacity to adapt to heat was found to be 1.261. A strong correlation was also observed between the sequential thermal index n(t) and the adaptive temperature. Finally, a new empirical model of adaptive temperature was developed using the data collected from a longitudinal survey in four residential buildings of APEI in summer, and the obtained adaptive temperature is 25.0 °C with upper and lower limits of 24.7 °C and 25.4 °C.

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Implications of Building Material Choice on Outdoor Microclimate for Sustainable Built Environment

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.650.82 ◽

2015 ◽

Vol 650 ◽

pp. 82-90 ◽

Cited By ~ 1

Author(s):

D. Kannamma ◽

A. Meenatchi Sundaram

Keyword(s):

Thermal Comfort ◽

Building Material ◽

Building Materials ◽

Climatic Factors ◽

Outdoor Environment ◽

Outdoor Thermal Comfort ◽

Physical Factors ◽

Physiological Equivalent Temperature ◽

Material Choice ◽

The Impact

The climatic conditions in a man-made urban environment may differ appreciably from those in the surrounding natural or rural environs.... each urban man-made buildings, roads, parking area, factories......creates around and above it a modified climate with which it interacts [1].Outdoor thermal comfort has gained importance in thermal comfort studies especially in tropical countries. In country like India, culturally the activities are spread both indoors and outdoors. Therefore the need for ambient outdoor environment gains importance. As there are many factors that contribute to outdoor thermal comfort (climatic factors and physical factors), this study aims in analyzing the impact of building material contribution, in an institutional courtyard. In order to understand the thermal contribution of various building materials and to suggest material choice to designers, ENVIMET is used for simulation purpose. The outdoor thermal comfort index employed in this study is PET (Physiological Equivalent Temperature), calibrated using RAYMAN.

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Importance of Behavioral Adjustments for Adaptive Thermal Comfort in a Condominium with HEMS System

Journal of the Institute of Engineering ◽

10.3126/jie.v15i3.32175 ◽

2020 ◽

Vol 15 (3) ◽

pp. 163-170

Author(s):

Rajan KC ◽

Hom Bahadur Rijal ◽

Masanori Shukuya ◽

Kazui Yoshida

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Energy Use ◽

Thermal Environment ◽

Residential Buildings ◽

Outdoor Environment ◽

Adaptive Behaviors ◽

Outdoor Air ◽

Indoor Thermal Environment ◽

Indoor Thermal Comfort

The energy use in residential dwellings has been increasing due to increasing use of modern electric appliances to make the lifestyle easier, entertaining and better. One of the major purposes of indoor energy use is for improving indoor thermal environment for adjusting thermal comfort. Along with the use of passive means like the use of mechanical devices, the occupants in any dwellings use active means such as the use of natural ventilation, window opening, and clothing adjustment. In fact, the use of active means when the outdoor environment is good enough might be more suitable to improve indoor thermal environment than the use of mechanical air conditioning units, which necessarily require electricity. Therefore, the people in developing countries like Nepal need to understand to what extent the occupants can use active means to manage their own indoor thermal comfort. The use of active means during good outdoor environment might be an effective way to manage increasing energy demand in the future. We have made a field survey on the occupants’ adaptive behaviors for thermal comfort in a Japanese condominium equipped with Home Energy Management System (HEMS). Online questionnaire survey was conducted in a condominium with 356 families from November 2015 to October 2016 to understand the occupants’ behaviors. The number of 17036 votes from 39 families was collected. The indoor air temperature, relative humidity and illuminance were measured at the interval of 2-10 minutes to know indoor thermal environmental conditions. The occupants were found using different active behaviors for thermal comfort adjustments even in rather harsh summer and winter. Around 80% of the occupants surveyed opened windows when the outdoor air temperature was 30⁰C in free running (FR) mode and the clothing insulation was 0.93 clo when the outdoor air temperature was 0⁰C. The result showed that the use of mechanical heating and cooling was not necessarily the first priority to improve indoor thermal environment. Our result along with other results in residential buildings showed that the adaptive behaviors of the occupants are one of the primary ways to adjust indoor thermal comfort. This fact is important in enhancing the energy saving building design.

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

Atmosphere ◽

10.3390/atmos11101101 ◽

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.

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A Review of the Impact of Vegetation in Solar Control towards Enhanced Thermal Comfort and Energy Performance in Buildings

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.887.428 ◽

2019 ◽

Vol 887 ◽

pp. 428-434

Author(s):

Dorcas A. Ayeni ◽

Olaniyi O. Aluko ◽

Morisade O. Adegbie

Keyword(s):

Thermal Comfort ◽

Adaptive Capacity ◽

Thermal Environment ◽

Thermal Conditions ◽

Building Design ◽

Energy Performance ◽

Tropical Region ◽

Indoor Climate ◽

Solar Control ◽

The Impact

Man requires a thermal environment that is within the range of his adaptive capacity and if this fluctuates outside the normal, a reaction is required beyond its adaptive capacity which results to health challenges. Therefore, the aim of building design in the tropical region is to minimize the heat gain indoors and enhance evaporative cooling of the occupants of the space so as to achieve thermal comfort. In most cases, the passive technologies are not adequate in moderating indoor climate for human comfort thereby relying on active energy technique to provide the needed comfort for the building users. The need for the use of vegetation as a panacea for achieving comfortable indoor thermal conditions in housing is recognised by architects globally. However, the practice by architects in Nigeria is still at the lower ebb. The thrust of this paper therefore is to examine the impact of vegetation in solar control reducing thermal discomfort in housing thereby enhancing the energy performance of the buildings. Using secondary data, the paper identifies the benefits of vegetation in and around buildings to include improvement of indoor air quality through the aesthetics quality of the environment and concludes that vegetation in and around building will in no small measure contributes to saving energy consumption.

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Experimental Investigation of Adaptive Thermal Comfort in French Healthcare Buildings

Buildings ◽

10.3390/buildings11110551 ◽

2021 ◽

Vol 11 (11) ◽

pp. 551

Author(s):

Zoubayre El Akili ◽

Youcef Bouzidi ◽

Abdelatif Merabtine ◽

Guillaume Polidori ◽

Amal Chkeir

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Winter Season ◽

Environmental Parameters ◽

Physical Parameters ◽

Predicted Mean Vote ◽

Adaptive Thermal Comfort ◽

Important Research Topic ◽

Radiant Temperature ◽

The Relationship

The thermal comfort requirements of disabled people in healthcare buildings are an important research topic that concerns a specific population with medical conditions impacted by the indoor environment. This paper experimentally investigated adaptive thermal comfort in buildings belonging to the Association of Parents of Disabled Children, located in the city of Troyes, France, during the winter season. Thermal comfort was evaluated using subjective measurements and objective physical parameters. The thermal sensations of respondents were determined by questionnaires adapted to their disability. Indoor environmental parameters such as relative humidity, mean radiant temperature, air temperature, and air velocity were measured using a thermal microclimate station during winter in February and March 2020. The main results indicated a strong correlation between operative temperature, predicted mean vote, and adaptive predicted mean vote, with the adaptive temperature estimated at around 21.65 °C. These findings highlighted the need to propose an adaptive thermal comfort strategy. Thus, a new adaptive model of the predicted mean vote was proposed and discussed, with a focus on the relationship between patient sensations and the thermal environment.

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