我国湿热地区人群基础热舒适反应研究(4):分体空调建筑人群的实验结果

采用气候室实验与现场调研相结合的方法,对我国湿热地区分体空调建筑人群进行了冬夏两季的气候室实验,针对当前环境、热经历、气候和季节4个适应要素展开了一系列对比分析,得到湿热地区人群的热适应特征为:季节和气候性适应体现在生理热反应上,前者表现为夏季与冬季相比心率下降,出汗量增多,皮肤温度下降,后者表现为与温带气候相比,湿热气候人群的出汗量减少,皮肤温度降低;环境控制度和热经历对心理热反应产生影响,较高控制度环境与较低控制度环境相比,较凉经历与较热经历相比,热感觉随环境的变化更敏感,可接受的热感觉范围更宽。     

严寒地区人体热适应性研究(3):散热器供暖环境下热反应实验研究

为了考察冬季供暖期间室外气温变化时不同室内温度对人体生理反应和心理热反应的影响,在散热器供暖的微气候室中,对受试者的皮肤温度、心率和血压等生理参数进行了测试,并对其热感觉和热舒适等主观热反应进行了问卷调查,研究供暖初期、中期和末期人体生理反应和心理热反应的变化规律。结果表明:随着冬季室外气温的下降,人们会更容易从心理上接受偏冷的环境,对室内温度期望不高,在相同的室内环境中感觉越来越热;相同的室外气温下,随着室内温度的降低,人体的皮肤温度会降低,心率下降;当室外气温下降而室内温度相同时,人体手臂皮肤温度显著升高,心率加快。说明随着冬季供暖期室外气温的逐渐降低,人们对偏冷环境的热适应性增强,这为严寒地区人体心理适应和生理习服提供了证据。     

干热干冷地区围护结构热工设计对内表面温度及室内热舒适的影响

为了分析干热干冷地区围护结构热工性能对室内热环境的影响,采用物理环境实测结合动态模拟方法对比分析了2组墙体的保温、蓄热性能对内表面温度的影响,并结合太阳辐射季节变化探究了太阳辐射吸收比对室内热舒适的影响。研究表明:实测结果与模拟结果吻合较好,对于干热干冷地区,提高围护结构蓄热性能能够降低夏季内表面温度,对冬季内表面温度影响不大;提高围护结构保温性能可以提升冬季内表面温度,同时引起夏季内表面温度升高,对夏季降温产生不利影响;围护结构月平均得热差值与太阳辐射月累计值显著相关,降低外表面太阳辐射吸收比有利于该地区建筑全年热环境的提升。     

高温高湿对湿热地区人群热湿反应的影响

针对湿热地区夏季高温高湿特点,对人群的热湿反应进行了气候室实验。选取30名大学生作为受试者,在不同高温(29,32℃)和高湿(50%,70%,90%)环境下获取受试者的热湿心理和生理反应。结果表明:温湿度交互作用对人体热湿反应有显著影响,温度越高,湿度对人体热湿反应的影响越大;湿热地区人群90%可接受的新有效温度ET*上限为30.3℃,80%可接受的ET*上限为32.3℃。     

干湿热气候自然通风建筑下人体热反应的对比研究

地区气候的差异性造成了不同地区人们的适应能力、热舒适需求及室内环境保障设计的差异要求。为了比较干热和湿热气候对人体热反应的影响,选择典型干热和湿热气候的农村住宅进行夏季热舒适的现场调研,共获得1 476套有效数据。结果表明:干热和湿热地区80%可接受温度上限分别为33. 6℃和31. 9℃,干热气候人们的耐热能力以及对高温的接受能力要高于湿热地区。在干热气候下极端高温作用下,增加湿度、加大风速均不利于人们热感觉的改善,但在湿热气候区,湿度对人们热感觉影响不大,温度越高,风速越大,越有利于改善人们的热感觉。在湿热地区,人们期望风速增加、期望温度降低的意愿比干热地区更为强烈。以上研究为干热和湿热地区热舒适标准的制定、被动式设计和室内热环境的设计提供了参考。     

水作用下热再生沥青混合料疲劳试验研究

通过对RAP掺量为40%的AC-16热再生沥青混合料进行马歇尔试验确定最佳沥青用量及配合比。针对浙江地区湿热多雨的气候环境,通过间接拉伸疲劳试验,研究高温浸水作用及温度作用对热再生混合料力学性能、疲劳寿命及疲劳特性的影响。试验结果表明,不同水作用及温度作用条件下热再生沥青混合料疲劳寿命与应力在双对数坐标下显线性关系;高温浸水作用及温度升高降低沥青再生混合料的疲劳寿命,与普通沥青混合料规律相似;应力水平在0.4时,水作用前后及温度变化对疲劳寿命差异影响最为显著;温度升高及水作用使疲劳系数k和n值降低,说明温度升高及水作用降低了热再生混合料的抗疲劳性能及疲劳寿命对应力的敏感程度。     

我国湿热地区人群基础热舒适反应研究(1):实验方法与结果

采用经典热舒适研究方法,于2008年夏季对我国湿热地区典型人群受试者作了气候室实验,在凉-暖范围内6个不同温湿度组合的工况下进行了问卷投票和生理指标测试。结果显示,受试者的热中性温度为26.9℃(修正温度);受试者夏季偏爱稍凉的热感觉(-0.2);潮湿感中性对应的水蒸气分压力约为3500Pa;热中性对应的平均皮肤温度为33.2℃;平均皮肤温度与皮肤湿润度是预测热感觉与热舒适的重要参数;心率与热感觉存在线性关系,血压在偏凉环境下与热感觉呈线性关系,在偏暖环境下变化不大。     

湿热湿冷地区住宅外遮阳设计策略研究

湿热湿冷地区气候特征表现为夏季湿热、冬季湿冷,大部分区域全年太阳辐射较低,且表现为夏季太阳辐射高,冬季太阳辐射低。从湿热湿冷地区的气候背景出发,对不同外遮阳形式对室内的隔热和采暖进行了实验研究,探索适宜湿热湿冷地区住宅建筑的外窗外遮阳形式。     

夏热冬冷地区建筑外廊对室内空间热环境影响分析——以夏热冬冷地区某建筑为例

建筑热环境状况直接影响着建筑的能耗。外廊作为建筑的交通和过渡空间,其对使用空间的热环境有一定的影响。本文以夏热冬冷地区有东侧外廊的某建筑为研究对象,采用实测的方法,分别在夏季和冬季采集室内外空间的热环境数据(空气温度、表皮温度等),通过对数据进行整理和分析,研究比对建筑的热环境特征,综合分析外廊夏季隔热和冬季保温效果的差异。实测结果表明,外廊对室内热环境有积极影响,在夏季具有良好的隔热效果,在冬季其保温效果有限。合理设计过渡空间有利于建筑热环境改善和建筑能耗的降低。     

教学组团夏季室外热环境特征与计算模型验证

对湿热地区典型教学组团的夏季室外热环境进行了33 h昼夜连续实测.根据气象参数,行人高度上温度、湿度、风速和湿球黑球温度（WBGT）分布以及典型地表温度等的测试结果,得到湿热地区教学组团夏季室外热环境的主要特征.测试结果表明,组团内的天井、架空、透水砖可有效降低夏季白天行人高度处的空气温度及WBGT,一些建筑设计手法对组团夏季白天室外热舒适的改善效果依次为：架空>天井>透水砖路面>不透水砖路面>混凝土路面.夜间,各测点的热舒适性基本一致.将测试结果对组团室外风速和WBGT现有计算模型进行验证研究.研究表明,数学公式计算值的相对误差均不超过6%,与实测统计值相吻合.     

我国湿热地区人群基础热舒适反应研究(2):研究结果的对比分析

基于我国湿热地区人群的气候室实验结果,从心理热反应、生理热反应和生理-心理关系等多方面对国内外研究结果进行了系统对比与分析,发现现行国际标准不适用于我国湿热地区,生理热习服和心理热适应是其重要原因。考虑热习服和热适应的影响作用,建立我国湿热地区人群的生理热调节模型与心理-生理模型,是掌握其基础热舒适反应规律、合理制定热环境标准的重要途径。     

The thermal mechanism of warm in winter and cool in summer in China traditional vernacular dwellings

Yaodong is one representative of western China vernacular dwellings. Its indoor thermal environment is cool in summer and warm in winter. This study interprets the characteristic of warm in winter and cool in summer in such a dwelling by measuring the indoor, outdoor and wall’s temperatures in winter and summer. The human thermal comfort theory is used to evaluate thermal environment, and the periodic heat transfer mechanism is used to analyze the thermal transfer through the wall. The results show that the Yaodong thick wall effectively damping external temperature wave and keeping steady inner surface temperature are the chief causes of warm in winter and cool in summer in Yaodong, which lays a scientific basis for low energy building design.     

A comparison of the thermal adaptability of people accustomed to air-conditioned environments and naturally ventilated environments

It has been reported previously that people who are acclimated to naturally ventilated (NV) environments respond to hot and warm environments differently than people who are acclimated to air-conditioned (AC) environments. However, it is not clear whether physiological acclimatization contributes to this discrepancy. To study whether living and working in NV or AC environments for long periods of time can lead to different types of physiological acclimatization, and whether physiological acclimatization has an important influence on people's responses of thermal comfort, measurements of physiological reactions (including skin temperature, sweat rate, heart rate variability, and heat stress protein 70) and thermal comfort responses were conducted in a 'heat shock' environment (climate chamber) with 20 people (10 in the NV group and 10 in the AC group). The results showed that the NV group had a significantly stronger capacity for physiological regulation to the heat shock than the AC group. In other words, the NV group did not feel as hot and uncomfortable as the AC group did. These results strongly indicate that living and working in indoor thermal environments for long periods of time affects people's physiological acclimatization. Also, it appears that long-term exposure to stable AC environments may weaken people's thermal adaptability. PRACTICAL IMPLICATIONS: This study examined the psychological and physiological differences of thermal adaptability of people used to air-conditioned environments and naturally ventilated environments. The results suggested that long-term exposure to stable air-conditioned environments may weaken people's thermal adaptability. Therefore, it might be advantageous for people to spend less time in static air-conditioned environments; this is not only because of its possible deleterious impact on people's physiological adaptability, but also because the air-conditioners' high-energy consumption will contribute to the effects of global warming.     

Research on seasonal indoor thermal environment and residents' control behavior of cooling and heating systems in Korea

Indoor thermal environments and residents' control behavior of cooling and heating systems were investigated in Seoul, Korea and compared with the results of previous studies. Twenty-four houses in summer, six houses in autumn and 36 houses in winter were used in this study. The measurement of temperature, humidity and air conditioner usage behavior was carried out. The clo-value, thermal comfort, sensation and basic data of the houses were also investigated. The indoor thermal environment in the summer had a high temperature and a high humidity ratio compare to standard comfort zone. Most of the indoor thermal environments at the time of starting the air conditioner in the summer were out of the comfort zone. Some of the data recorded while the air conditioner was stopped were in the comfort zone, but in many cases the temperature was relatively higher than comfort zone. Most indoor climate distributions in the winter were in the comfort zone and the indoor climate in autumn coincided well with the criteria of the comfort zone. Compared with results of previous studies in these 25 years, indoor ambient average temperature in winter has increased and the comfort temperature has increased in the heating period and decreased in the cooling period. This result indicates that the development of an HVAC system has created an expectation of comfort for residents and has shifted their thermal comfort zone warmer in winter and cooler in summer.     

Thermal comfort of people in the hot and humid area of China—impacts of season,climate, and thermal history

We conducted a climate chamber study on the thermal comfort of people in the hot and humid area of China. Sixty subjects from naturally ventilated buildings and buildings with split air conditioners participated in the study, and identical experiments were conducted in a climate chamber in both summer and winter. Psychological and physiological responses were observed over a wide range of conditions, and the impacts of season, climate, and thermal history on human thermal comfort were analyzed. Seasonal and climatic heat acclimatization was confirmed, but they were found to have no significant impacts on human thermal sensation and comfort. The outdoor thermal history was much less important than the indoor thermal history in regard to human thermal sensation, and the indoor thermal history in all seasons of a year played a key role in shaping the subjects' sensations in a wide range of thermal conditions. A warmer indoor thermal history in warm seasons produced a higher neutral temperature, a lower thermal sensitivity, and lower thermal sensations in warm conditions. The comfort and acceptable conditions were identified for people in the hot and humid area of China.     

Seasonal effects of urban street shading on long-term outdoor thermal comfort

As shading, an important factor in urban environments, affects thermal environments and long-term thermal comfort, this study conducted several field experiments to analyze the outdoor thermal conditions on urban streets in central Taiwan. The RayMan model was utilized for predicting long-term thermal comfort using meteorological data for a 10-year period. Analytical results indicate that slightly shaded areas typically have highly frequent hot conditions during summer, particularly at noon. However, highly shaded locations generally have a low physiologically equivalent temperature (PET) during winter. Correlation analysis reveals that thermal comfort is best when a location is shaded during spring, summer, and autumn. During winter, low-shade conditions may contribute to the increase in solar radiation; thus, thermal comfort is improved when a location has little shade in winter. We suggest that a certain shading level is best for urban streets, and trees or shade devices should be used to improve the original thermal environment.     

Development of an adaptive thermal comfort equation for naturally ventilated buildings in hot-humid climates using ASHRAE RP-884 database

The objective of this study was to develop an adaptive thermal comfort equation for naturally ventilated buildings in hot-humid climates. The study employed statistical meta-analysis of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) RP-884 database, which covered several climatic zones. The data were carefully sorted into three climate groups including hot-humid, hot-dry, and moderate and were analyzed separately. The results revealed that the adaptive equations for hot-humid and hot-dry climates were analogous with approximate regression coefficients of 0.6, which were nearly twice those of ASHRAE and European standards 55 and EN15251, respectively. The equation using the daily mean outdoor air temperature had the highest coefficient of determination for hot-humid climate, compared with other mean temperatures that considered acclimatization of previous days. Acceptable comfort ranges showed asymmetry and leaned toward operative temperatures below thermal neutrality for all climates. In the hot-humid climate, a lower comfort limit was not observed for naturally ventilated buildings, and the adaptive equation was influenced by indoor air speed rather than indoor relative humidity. The new equation developed in this study can be applied to tropical climates and hot-humid summer seasons of temperate climates.     

Comfort,perceived air quality,and work performance in a low-power task–ambient conditioning system

Zhang's thermal comfort model [Zhang H. Human thermal sensation and comfort in transient and non-uniform thermal environments, Ph.D. thesis, UC Berkeley; 2003. 415 pp.] predicts that the local comfort of feet, hands, and face predominates in determining a person's overall comfort in warm and cool conditions. We took advantage of this in designing a task–ambient conditioning (TAC) system that heats only the feet and hands, and cools only the hands and face, to provide comfort in a wide range of ambient environments. Per workstation, the TAC system uses less than 41 W for cooling and 59 W for heating. We tested the TAC system on 18 subjects in our environmental chamber, at temperatures representing a wide range of practical winter and summer conditions (18–30 °C). A total of 90 tests were done. We measured subjects' skin and core temperatures, obtained their subjective responses about thermal comfort, perceived air quality, and air movement preference. The subjects performed three different types of tasks to evaluate their productivity during the testing. The TAC system maintains good comfort levels across the entire temperature range tested. TAC did not significantly affect the task performance of the occupants compared to a neutral ambient condition. Whenever air motion was provided, perceived air quality was significantly improved, even if the air movement was re-circulated room air. In our tests, subjects found thermal environments acceptable even if they were judged slightly uncomfortable (−0.5). By reducing the amount of control normally needed in the overall building, the TAC system saves energy. Simulated annual heating and cooling energy savings with the TAC system are as much as 40%.     

国内高校建筑热环境现场研究的现状及展望

本文从主客观两方面,对近年高校建筑的热环境现场研究进行了总结,着重分析了不同地域、研究对象等情况下的热环境状况,做出了全面的综述。目前,我国校园建筑热环境研究还不够全面。未来应该进一步对夏热冬暖、温和地区这两个气候区进行研究,并丰富现场研究的调查方式。从业人员可以基于测试者生理,心理反馈及调节行为,制定适应不同气候、不同对象的评价指标。     

Field study on occupants’ thermal comfort and residential thermal environment in a hot-humid climate of China

This paper discusses thermal comfort inside residences of three cities in the hot-humid climate of central southern China. Only a few thermal comfort studies have been performed in hot-humid climates and none in Central Southern China. Field sampling took place in the summers of 2003 and 2004 by obtaining 110 responses to a survey questionnaire and measuring environmental comfort variables in three rooms in each of 26 residences. The objectives are to measure and characterize occupant thermal perceptions in residences, compare observed and predicted percent of dissatisfied and discern differences between this study and similar studies performed in different climate zones. Average clothing insulation for seated subjects was 0.54 clo with 0.15 clo of chairs. Only 48.2% of the measured variables are within the ASHRAE Standard 55-1992 summer comfort zone, but approximately 87.3% of the occupants perceived their thermal conditions acceptable, for subjects adapt to prevailing conditions. The operative temperature denoting the thermal environment accepted by 90% of occupants is 22.0–25.9°. In the ASHRAE seven-point sensation scale, thermal neutral temperature occurs at 28.6°. Preferred temperature, mean temperature requested by respondents, is 22.8°. Results of this study can be used to design low energy consumption systems for occupant thermal comfort in central southern China.