Adaptive thermal comfort in Australian school classrooms

This survey of thermal comfort in classrooms aimed to define empirically the preferred temperatures, neutral temperatures and acceptable temperature ranges for Australian school children, and to compare them with findings from adult populations. The survey was conducted in a mixture of air-conditioned, evaporative-cooled and naturally ventilated classrooms in nine schools located in three distinct subtropical climate zones during the summer of 2013. A total of 2850 questionnaires were collected from both primary (grade) and secondary (high) schools. An indoor operative temperature of about 22.5°C was found to be the students’ neutral and preferred temperature, which is generally cooler than expected for adults under the same thermal environmental conditions. Despite the lower-than-expected neutrality, the school children demonstrated considerable adaptability to indoor temperature variations, with one thermal sensation unit equating to approximately 4°C operative temperature. Working on the industry-accepted assumption that an acceptable range of indoor operative temperatures corresponds to group mean thermal sensations of ?0.85 through to +0.85, the present analysis indicates an acceptable summertime range for Australian students from 19.5 to 26.6°C. The analyses also revealed between-school differences in thermal sensitivity, with students in locations exposed to wider weather variations showing greater thermal adaptability than those in more equable weather districts.     

The effect of Urban Heat Island mitigation strategies on outdoor human thermal comfort in the city of Baghdad

Todays, most Iraqi cities suffer from extremely hot-dry climate for long periods throughout the year. However, most urban patterns that exist inside these cities are not suitable for this harsh conditions and lead to an increase in the value of the Urban Heat Island (UHI) index. Consequently, this will increase outdoor human thermal discomfort as well as energy consumption and air pollution in cities. This study attempts to evaluate the effect of UHI mitigation strategies on outdoor human thermal comfort in three different common types of urban patterns in the biggest and most populated city in Iraq, Baghdad. Three different mitigation strategies are used here – vegetation, cool materials, and urban geometry – to build 18 different scenarios. Three-dimensional numerical software ENVI-met 4.2 is utilised to analyse and assess the studied parameters. The input data for simulations process are based on two meteorological stations in Baghdad: Iraqi Meteorological Organization & Seismology, and Iraqi Agrometeorological Network. All measurements are taken in a pedestrian walkway. The results of different scenarios are compared based on their effect on human thermal comfort. Outdoor thermal comfort is assessed according to Predicted Mean Vote index, as mentioned in ISO 7730 standard. This study provides a better understanding of the role of UHI mitigation strategies on human thermal comfort in the outdoor spaces of Baghdad's residential neighbourhoods. This can help generate guidelines of urban design and planning practices for better thermal performance in hot and dry cities.     

Revisiting thermal comfort models in Iranian classrooms during the warm season

The validity of existing thermal comfort models is examined for upper primary school children in classroom settings. This is of importance to enhance productivity in the learning environment and to improve the control of artificial heating and cooling, including the potential for energy savings. To examine the thermal perceptions of children aged 10–12 years in non-air-conditioned classrooms, three sets of field experiments were conducted in boys’ and girls’ primary schools in Shiraz, Iran. These were undertaken during regular class sessions covering cool and warm conditions of the school year, polling responses from 1605 students. This paper illustrates the overall methods and reports the results of the warm season field survey (N?=?811). This investigation suggests that predicted mean vote-predicted percentage of dissatisfied (PMV/PPD) underestimates children's actual thermal sensation and percentage dissatisfied in the investigated classrooms. The analysis shows that sampled children may be slightly less sensitive to indoor temperature change than adults. The upper acceptable temperature derived from children's responses corresponding to mean thermal sensations of +0.85 is 26.5°C, which is about 1°C lower than the ASHRAE upper 80% acceptability limit. This implies that sampled children feel comfortable at lower temperatures than predicted by the ASHRAE Adaptive model during the warm season.     

Adaptive-rational thermal comfort model: Adaptive predicted mean vote with variable adaptive coefficient

Thermal adaptations, as feedbacks of occupants to physical stimuli, extend thermal comfort zone thereby reducing building energy consumption effectively. The rational approach models thermal comfort from the perspective of the body's heat balance, but is limited in explaining the thermal adaptations. The adaptive approach of modeling thermal comfort can fully account for the thermal adaptations, but ignores the body's heat balance. To improve thermal comfort prediction, this study proposes an adaptive-rational thermal comfort model, that is, an adaptive predicted mean vote with a variable adaptive coefficient (termed as arPMV). By linearly linking the negative feedback effects of the thermal adaptations to the ambient temperature according to the adaptive approach, the variable adaptive coefficient is linearly related to the reciprocal of the ambient temperature with two constants. The variable adaptive coefficient is determined by explicitly quantifying the two constants as the functions of the predicted mean vote, thermal sensation vote, and ambient temperature. The proposed arPMV is validated for naturally ventilated, air-conditioned, and mixed-mode buildings, with the mean absolute error and the robustness of the thermal sensation prediction reduced by 24.8%-83.5% and improved by 49.7%-83.4%, respectively.     

严寒地区居住建筑室内热舒适模拟研究

将模拟计算得到的模型房间的温度场与经回归分析建立的平均热感觉MTS预测模型和热舒适评价指标PMV相结合,通过编制MATLAB程序,绘制了模型房间不同截面的MTS和PMV的三维分布图。比较了各个截面的MTS和PMV预测结果并分析了产生误差的原因。     

Building envelope regulations on thermal comfort in glass facade buildings and energy-saving potential for PMV-based comfort control

This paper presents an investigation of the effect of building envelope regulation on thermal comfort and on the energy-saving potential for PMV-based comfort control in glass facade buildings. Occurrences and severity of overheating, based on the PMV-PPD model contained in ISO 7730, were used for the thermal comfort assessment. Parametric study simulations for an actual building with a large glass facade were carried out to predict the changes in thermal comfort levels in a space due to different glazing types, depths of overhang and glazing areas, which are the key parameters of the building envelope regulation index, named ENVLOAD, in Taiwan. The result demonstrates that the ENVLOAD has significant effect on thermal comfort. Additionally, comparative simulations between PMV-based comfort control and conventional thermostatic control were performed to investigate the changes in the energy-saving potential of a thermal comfort-controlled space due to changes of its ENVLOAD. The results demonstrate that the energy-saving potential in a PMV-based controlled space increases with low ENVLOAD conditions.     

Adaptive analysis of thermal comfort in university classrooms: Correlation between experimental data and mathematical models

Numerous studies are in progress to support adaptive models in indoor thermal comfort evaluation and to establish quantitative indexes to allow the subject to optimize his/her comfort conditions.     

由热舒适指标及空调设计计算参数谈节能

以PMV—PPD评价指标和ASHRAE舒适标准为理论依据，对空调设计舒适度和空调节能进行了讨论，认为应研究适于我国居民的热舒适标准，而后提出一些节能措施以及方向。     

自然通风环境下的热舒适分析

鉴于自然通风环境下的PMV实际热舒适调查结果有较明显的偏差，热舒适研究领域提出了两种新的模型：PMV修正模型和适应模型。对这两种模型进行了分析，认为应对自然通风环境和空调稳态环境参数进行更细致的分析，以建立一种适用于自然通风环境的集总参数模型或评价指标。     

厦门高校教室冬季热环境测试及热舒适预测

为考察冬季非空调环境下人体热感觉,对厦门某高校教室的热舒适度进行了现场测试.在测量室内外热舒适参数的同时,通过问卷调查得到了人体热反应样本.分析样本得出厦门高校教室冬季非空调工况下人体热中性温度和热期望温度分别为19.3和19.4℃.综合考虑温度、相对湿度、平均辐射温度、风速及服装热阻对坐姿轻度活动状态人体的热舒适影响,使用MATLAB软件进行非线性回归,得到非空调工况下热舒适预测方程.该预测方程与实测得到的人体热舒适投票两者结果有较高相关度,同时较大程度上反映了冬季非空调环境下人体热感觉的变异.     

Perception of the thermal environment in high school and university classrooms: Subjective preferences and thermal comfort

This work shows some of the results of a field study about environmental comfort investigations in classrooms. In this project thermal, acoustic, visual and air quality aspects were analysed in a number of classrooms—13 classrooms at four different high schools of the Provincia di Torino and four typical medium-sized university classrooms of the Politecnico di Torino, Italy. The investigations were carried out during the heating period. Both field measurements and subjective surveys were performed at the same time during the regular lesson periods.     

Adaptive use of natural ventilation for thermal comfort in Indian apartments

Thermal comfort research in India is in its nascent stage. Indian codes specify uniform comfort temperatures between 23 and 26 °C for all types of buildings. About 73% of energy in Indian residences is consumed for ventilation and lighting controls. Therefore, a thermal comfort field survey was conducted in apartment buildings in Hyderabad, which included information on the use of building controls. The present analysis is based on this database. Due to the poor availability of adaptive opportunities, 60% of the occupants were uncomfortable in summer. The comfort range obtained (26.0–32.5 °C) was way above the standard.     

北京地区大学教室热舒适长期调查研究

针对北京市某大学的教室进行调研,对室内热环境参数、受访者服装热阻及受访者热感觉投票进行了为期1年的跟踪调查。试图通过探索教室热环境参数与受访者热感觉之间的关系了解受访者对教室内热环境的需求,结果发现,不同季节受访者对环境的需求存在差异,夏季空调环境人体中性温度为26.9℃,过渡季节自然通风环境中性温度为23.5℃,而冬季集中供热环境中性温度为22.9℃,着装量不同是造成上述差异的主要原因。对于室内环境控制,在春秋过渡季节的绝大多数时间,自然通风可满足人员对室内热环境的需求;在非自然通风季节,将室内温度控制到可接受的范围就可以满足多数受访者的需求。     

上海地区村镇住宅热环境与热舒适度研究

利用现场实测方法,对上海一典型村庄进行了夏季及冬季住宅热环境以及居民热舒适性现场实测及调研,研究了上海地区农村住宅热环境及室内热舒适度问题。依据问卷调研结果得到了夏季、冬季农村居民对于住宅环境的可接受温度范围、热中性温度以及期望温度,同时研究了热舒适度的影响因素,可为上海地区村镇住宅节能计算、热舒适环境与绿色生态住宅的设计提供必要的理论依据。     

Measurements and simulations of thermal comfort: a synagogue in Tel Aviv,Israel

This study illustrates the utility of empirical and digital methodologies in examining the question to which degree an architect who lives and builds in one distinctive geographic and climatic region adapts his sacred architecture design to a different climatic region. Specifically, we analysed the thermal comfort in a Synagogue in Tel Aviv, Israel, designed by a renowned Swiss architect in 1996. The morphological analyses, actual measurements, and computerized energy simulations show that the synagogue exhibits high thermal discomfort during the hot-humid summers in Tel Aviv. The results of morphological analyses and simulations also show thermal discomfort in the synagogue during Tel Aviv's mild winters. When simulating the synagogue as if built in Switzerland, the results also show high thermal discomfort. Thus, the design of this synagogue did not necessarily consider climate conditions. However, the design does exhibit attentiveness and sensitivity to symbols and faith requirements.     

Thermal comfort in Italian classrooms under free running conditions during mid seasons: Assessment through objective and subjective approaches

This work shows the results of a field study about indoor thermal comfort, based on investigations in Italian classrooms. The surveys were carried out in Turin, in the North–West of Italy. The monitoring campaigns were performed during the mid season, in free running conditions. This study follows a previous one based on a monitoring campaign performed during the heating season. The responses from these two different configurations were integrated, analyzed and compared.     

重庆自然通风热舒适模型的建立及热环境评价

在分析国内外自然通风热舒适研究的基础上,结合重庆地区潮湿的气候特点,对现有自然通风热舒适评价模型进行了湿度修正.采用电子温湿度记录仪对重庆地区村镇典型住宅的室内外热湿参数进行了全年监测,并利用该模型对村镇住宅的室内热环境进行了评价.分析表明,村镇住宅室内和室外相对湿度高于70％的时间分别占全年总时间的95.4％和87.2％,室内温度高于28℃且相对湿度高于70％的时间达1 196 h;全年舒适时间为3 838 h,占全年总时间的43.8％;现有评价模型与修正模型的舒适时间相差405 h,其中空调季相差342h,且温度越高,相对湿度对热舒适的影响越大,说明在温度较高时应考虑相对湿度对热舒适的影响,但修正模型的可靠性还需进一步验证.     

非空调环境下性别与热舒适的关系

对长沙某高校的600多名学生进行了为期一年的现场问卷调查,对有关空气参数进行了测量。统计分析结果表明,女性的耐寒能力比男性差;预期平均评价PMV指标对男女热感觉的预测效果较差;男女对湿感觉的评价无较大差异,只在温度较低时,女性比男性觉得更潮湿;女性的吹风感比男性强;热舒适评价不仅受热、湿感觉影响,还受其他环境因素及心理因素的影响。     

高校图书馆夏季热环境分析及改善措施研究

通过对高校图书馆室内外热环境的测试，阐明了建筑物夏季热环境现状，根据所测数据分析了引起室内过热的原因，并提出了解决和改善措施，并为其他公共建筑（主要以白天使用为主）的热环境改善提供参考，实现室内外环境协调可持续发展。