Optimisation of Thermal Comfort of Building in a Hot and Dry Tropical Climate: A Comparative Approach between Compressed Earth/Concrete Block Envelopes

Compressed earth blocks (CEB) are an alternative to cement blocks in the construction of wall masonry. However, the optimal architectural construction methods for adequate thermal comfort for occupants in hot and arid environments are not mastered. This article evaluates the influence of architectural and constructive modes of buildings made of CEB walls and concrete block walls, to optimize and compare their thermal comfort in the hot and dry tropical climate of Ouagadougou, Burkina Faso. Two identical pilot buildings whose envelopes are made of CEB and concrete blocks were monitored for this study. The thermal models of the pilot buildings were implemented in the SketchUp software using an extension of EnergyPlus. The models were empirically validated after calibration against measured thermal data from the buildings. The models were used to do a parametric analysis for optimization of the thermal performances by simulating plaster coatings on the exterior of walls, airtight openings and natural ventilation depending on external weather conditions. The results show that the CEB building displays 7016 hours of discomfort, equivalent to 80.1% of the time, and the concrete building displays 6948 hours of discomfort, equivalent to 79.3% of the time. The optimization by modifications reduced the discomfort to 2918 and 3125 hours respectively;i.e. equivalent to only 33.3% for the CEB building and 35.7% for the concrete building. More study should evaluate thermal optimizations in buildings in real time of usage such as residential buildings commonly used by the local middle class. The use of CEB as a construction material and passive means of improving thermal comfort is a suitable ecological and economical option to replace cementitious material.

An Expandable,Contextualized and Data-Driven Indoor Thermal Comfort Model

Continuous discrepancies in building performance predictions creates an ongoing inclination to link contextu-alized,real-time inputs and users’feedback for not only building control systems but also for simulation tools.It is now seeming necessary to develop a model that can record,find meaningful relationship and predict more holistic human interactions in buildings.Such model could create capacity for feedback and control with a level of intelligence.Fuzzy Logic Systems(FLSs)are known as robust tools in decision making and developing models in an efficient manner.Considering this capability,in this paper,FLSs is implemented to make a thermal comfort model in an educational building in the UK.Such implementation has an ability to respond to some identified desires of developers and performance assessors in addressing uncertainty in thermal comfort models.The results demonstrate the proposed method is practical to simulate the value of comfort level based on the input data.

A day-ahead scheduling framework for thermostatically controlled loads with thermal inertia and thermal comfort model

This paper proposes a day-ahead dispatch framework of thermostatically controlled loads(TCLs) for system peak load reduction. The proposed day-ahead scheduling framework estimates the user’s indoor thermal comfort degree through the building thermal inertia modelling. Based on the thermal comfort estimation, a dayahead TCL scheduling model is formulated, which consists of 3 stages: TCL aggregator estimates maximal controllable TCL capacities at each scheduling time interval by solving a optimization model;[ the system operator performs the day-ahead system dispatch to determine the load shedding instruction for each aggregator;and ′the TCL aggregator schedules the ON/OFFcontrol actions of the TCL groups based on the instruction from the system operator. A heuristic based optimization method, history driven differential evolution(HDDE)algorithm, is employed to solve the day-ahead dispatch model of the TCL aggregator side. Simulations are conducted to validate the proposed model.

Field study of seasonal thermal comfort and adaptive behavior for occupants in residential buildings of Xi’an,China

The study aims to investigate the thermal comfort requirements in residential buildings and to establish an adaptive thermal comfort model in the cold zone of China.A year-long field study was conducted in residential buildings in Xi’an,China.A total of 2069 valid questionnaires,along with indoor environmental parameters were obtained.The results indicated occupants’thermal comfort requirements varied with seasons.The neutral temperatures were 17.9,26.1(highest),25.2,and 17.4℃(lowest),and preferred temperatures were 23.2,25.6(highest),24.8,and 22.4℃(lowest),respectively for spring,summer,autumn,and winter.The neutral temperature and preferred temperature in autumn are close to the neutral temperature in summer,while the neutral temperature and preferred temperature in spring are close to that in winter.Besides,the 80%and 90%acceptable temperature ranges,adaptive thermal comfort models,and thermal comfort zones for each season were established.Human’s adaptability is related to his/her thermal experience of the current season and the previous season.Therefore,compared with the traditional year-round adaptive thermal comfort model,seasonal models can better reflect seasonal variations of human adaptation.This study provides fundamental knowledge of the thermal comfort demand for people in this region.

Thermal Comfort in Waiting Room at Railway Station in Cold Region in China

A field study and analysis about the thermal comfort was carried out in the waiting room at Beijing West Rail Station in Chinese cold region.Passengers' TSV(thermal sense vote)was obtained using statistical method on the basis of more than 1 200 questionnaires.The linear regression between TSV and indoor temperature indicates that thermal neutral temperature is 25.2 ℃.According to the percentage of satisfaction among all passengers under different indoor temperatures,the acceptable temperature range in the waiting room is 24.2～30.2℃.It is also found that passengers' temporary stay should be taken into consideration for the thermal comfort analysis.Passengers' TSV is not a constant value after they enter the waiting room.In fact,ΔTSV increases as passengers are waiting for the train,and the growing rate is dependent on indoor-outdoor temperature difference.The greater the temperature difference,the faster ΔTSV increases.At last,a linear regression between indoor comfortable temperature and outdoor temperature was generated as the adaptive comfort model.

Research on the Winter Thermal Comfort of Library's Atrium Reading Space in Harbin Universities

As a transition space,atrium not only organizes traffic,makes the flow line flexible,but also modulates the indoor micro-climate. Because of its good sense of space and lighting performance,designers generally set reading space around the atrium. But nowadays,people are more concerned with the external form of the architecture,rather than the thermal comfort conditions of the atrium reading space. This article chooses the universities' library atrium space of Harbin in typical city in cold regions as the carrier of research,testes the thermal environment of atrium reading space, analyzes the user 's subjective feelings of the thermal environment and establishes climate adaptation model applied to library buildings. This paper aims to study on Winter thermal comfort of universities' library atrium reading space in cold area. Bases on thermal comfort adaptive model,it establishes a reasonable heating methods and design temperature index of indoor thermal environment. Optimum comfort is obtained while achieving building energy efficiency and providing viewers a comfortable reading space.

Evaluation of Thermal Effect of PCM Wallboards by Coupling Simplified Phase Change Model with Design Tool

A simplified PCM wallboard model is coupled to an existing design-oriented model of multi-zone buildings. Using a reference model and a basic simulation configuration, the accuracy of the resulting PCM wallboard-building thermal design tool is evaluated. A new performance indicator, called PCM utilization factor, is then proposed in order to estimate the thermal efficiency of using PCM wallboards in buildings. Using this PCM Utilization factor and a degrees-hours indicator, the ability of the PCM wallboard-building thermal design tool to evaluate the effect of PCM wallboards on heating loads and summer thermal comfort in the early design phase of a project is examined in two real case studies: a family house project and an existing office building. The user-friendliness of this design tool, and the short calculation times it leads to when performing a year-long simulation using a standard office computer, make it a well-adapted tool for sensibility studies or multi-criterion optimization for buildings that contain PCM wallboards.

Analysis of Thermal Behavior of Materials in the Building Envelope Using Building Information Modeling (BIM)—A Case Study Approach

Building envelope is a fence that controls heat exchange between interior and exterior and plays an essential role in providing thermal comfort conditions of residents. In recent years, due to the necessity of conserving energy and also preventing increased environmental pollution, the importance of sustainable construction has been doubled. Checking the problems of thermal behavior of the building envelope materials, and what influences in the heating and cooling loads exerted and energy consumption of buildings, are the questions that this research seeks to answer. In this regard, building information modelling analysis (BIM) has worthy contribution in the completion process of sustainable design;thus using software Design Builder, it is paid attention to simulation of the thermal behavior of two types of defined materials for the building envelope that was designed as a Research Institute of Renewable Energy of Yazd University. For Type 1 materials, two layers of brick have been selected, and for Type 2 a thermal insulation layer also added it. Results of the analysis showed that the use of materials Type 2 in the cooling load %4.8 and in the thermal load %62.5 reduction can be achieved which means reducing the load on active system and thus reducing the initial cost of building. Also reduction in annual energy consumption by almost %2.4 for cooling and %62.9 for heating buildings have been achieved, which makes saving non-renewable energy consumption, and consequently reducing environmental pollution as well as reducing current costs will be established.

夏季华东地区室外热舒适经验指标模型建立

伴随国民经济水平的提高,室外的热舒适水平逐渐受到民众的广泛关注。尤其是在经济发达的华东地区,人口密集,夏季的炎热气候严重影响了民众在室外空间的热舒适与体验。已有研究表明,在一些地区,基于当地调研数据建立的经验指标模型能够更好地预测当地民众的室外热舒适状况。因此,文章对华东地区代表性城市金华市展开微气候环境测量与问卷调查,利用统计学方法多元回归对调研数据进行分析,最终建立经验指标模型并验证其适用性。研究结果表明,在回归分析得出的三个模型中,选取拟合度最优的模型为经验指标模型,具体公式为:TSV_(model)=0.228T_(a)-0.211V+0.201T_(g)-13.947(R^(2)=0.715,P<0.001)。所得经验指标模型为夏季华东地区基于室外热舒适的空间优化设计研究提供了评价指标选择的参考。

蒸发冷却空调的热舒适评价方法综述及展望

在绿色节能的新形势下,蒸发冷却空调相比于传统空调更具有节能减排的优势。目前关于蒸发冷却空调的研究仍集中于系统性能和能效上,而忽略了其所营造的室内环境的热舒适情况。准确预测蒸发冷却空调的热舒适对其发展同样起着不可忽视的作用。文章介绍了国内外蒸发冷却空调的热舒适研究现状并综述了其采用的热舒适评价方法,分析了蒸发冷却空调采用适应性热舒适评价的可能性和必要性。针对蒸发冷却空调所营造的室内热环境特点,提出了蒸发冷却系统的适应性热舒适模型框架。

西安地区开放式办公建筑夏季人体热舒适调查研究

以西安地区6栋典型开放式办公建筑为研究对象,通过热环境参数测试和主观问卷调查相结合的方式进行了现场调研,分析了实际办公建筑中人员的热舒适需求,并将调研结果与现有标准及其他气候区现场研究进行了对比。结果显示,西安地区夏季办公建筑受访者的中性温度为25.4℃,偏好温度比中性温度低0.2℃,80%可接受温度上限为28.2℃。

基于暖体假人的套装局部热阻及预测模型研究

对多名成年男女全年各季节着装行为进行了现场调研,得到了我国成年男女全年各季节典型着装搭配情况。在实验室条件下利用暖体假人模型进行了各季节典型着装搭配下的套装热阻测试,得到了34组成套服装的整体与局部热阻值,建立了全年各季节典型套装的局部服装热阻数据库。在此基础上分析了套装局部与整体热阻值的关系,获得了基于套装整体热阻值的局部热阻预测模型。

热感觉对气候温和地区热舒适模型的修正作用研究

为探究气候温和地区高校教室内的热舒适性,且修正预测热感觉和不满意度模型(predicted mean vote-predicted percentage of dissatisfaction,PMV-PPD模型)与实际热感觉投票值存在偏差情况,本文以昆明某高校大学生受试者为试验对象,分别测试室内环境参数、人员评估环境温度(t_(1))以及受试者主观评价等,共获得2229份有效数据。结果表明:在自然通风教室中,超过80%的大学生可以接受当前的热湿环境,PMV与实际平均热感觉投票(mean thermal sensation,MTS)模型相关较弱,PMV模型高估了受试者的实际热感觉,实测人员不满意百分比普遍大于预测不满意百分比。鉴于PMV模型预测准确性较低,综合考虑温度变化、主观反应等影响因素,提出人员评估环境温度(t_(1))作为修正性指标。人员评估环境温度与实际环境温度存在较强相关性,且在不同场景中两者温差值小于1.5℃。将t_(1)与热感觉投票进行回归分析,该参数与热感觉投票高度相关。在PMV计算中使用t_(1)代替空气温度对PMV模型进行修正得到tPMV,修正后的tPMV更接近于MTS模型,对PMV起到显著有效的修正作用。

基于热舒适的建筑外墙隔热设计参数研究

给出了夏热冬冷地区和寒冷地区4个典型城市的热适应模型与热可接受温度区间。对4个城市的常见围护结构进行了调研,基于夏季典型设计日室外空气温度动态变化,得到了不同围护结构内表面温度的逐时变化值。基于热适应模型,确定了不同气候区典型城市常见围护结构人可接受的最高内表面温度,并与现行相关规范进行了对比分析。结果显示,上海市和西安市规范所规定的自然通风环境下围护结构内表面最高温度无法满足人员热舒适要求,规范规定限值应进行适当下调。

考虑热舒适度的居民空调负荷调控潜力差异化评估

居民空调负荷是电力系统重要的灵活性资源,评估其调控潜力有助于负荷高效管理,促进节能减排。然而,受资金成本、数据存储和隐私保护等因素制约,居民空调状态及参数难以直接测量,差异化评估不同居民空调负荷的调控潜力存在困难。此外,居民使用空调是为了满足自身的热舒适度要求。若评估空调负荷调控潜力时忽视热舒适度限制,将导致评估值过高,降低负荷管理策略的有效性。因此,提出一种考虑热舒适度的居民空调负荷调控潜力差异化评估方法。该方法首先建立居民热舒适度及空调热动力学模型,提取影响居民热舒适度和空调负荷的关键参数;然后,利用隐马尔可夫模型和维特比算法辨识空调状态及参数;在此基础上,计算不同居民热舒适度可接受范围内的空调负荷调控潜力。基于真实居民负荷数据的算例分析表明,所提方法能够准确辨识居民空调状态并有效评估满足居民热舒适度要求的空调负荷调控潜力。

后疫情下公交、地铁和高铁中佩戴口罩对乘员热舒适影响的评估

在后疫情时代,佩戴口罩成为人们进出公共场所的重要防疫措施,特别是在乘坐大流量、高密度的城内与城际公共交通时。面部与口罩之间高湿且相对密闭的微环境对乘员热舒适会产生重要影响。本文根据佩戴口罩时热舒适指标的变化对PMV-PPD模型进行了校正,并将校正后的模型应用于公共交通的热舒适评估。结果表明:在公交车和地铁内佩戴医用口罩时,对热舒适的影响分别表现为降低和提升,预测不满意百分数平均差值分别为6%、-7%;高铁内热舒适表现为微小提升,平均差值为-0.5%;公交车、地铁和高铁内乘员的热舒适区占比分别为62.5%、27.1%、92.5%,表明高铁对热舒适环境的控制效果最佳。

基于舒适节能控制的分体式空调建模与仿真

分体式空调在住宅和办公室应用非常广泛,耗费电能数量巨大。然而绝大部分空调并不具备最佳运行策略,在运行过程中存在着很大的电能浪费问题,因此采用合适的空调控制策略使空调运行在既节能又舒适的状态上就显得尤为重要。于是着眼于保障舒适性并降低房间空调器的能耗,首先分析空调运行状态,建立房间环境模型和分体式空调运行模型,然后通过按需启停和适当调整空调温度设定值等方法对空调进行控制,最后对仿真结果进行分析得出使室内环境维持舒适且节能的基于规则的最优运行控制策略。

协同考虑空气质量与热舒适度的暖通空调系统双层优化控制策略

暖通空调(HVAC)系统作为智能楼宇的耗能主体,实现其能耗成本与用户舒适度的灵活权衡具有重要意义。然而,并行考虑以上两种因素时,系统优化模型的耦合项增加,求解难度增大。基于学习的控制策略在模型构建上具有便捷性,但节能效果一般。面对以上挑战,提出协同考虑空气质量与热舒适度的HVAC系统双层优化控制策略。首先,基于RC等效电路的热动态模型和楼宇内部物理结构,精确刻画各区域温度和空气质量的耦合关系;然后,以能耗成本最低及用户舒适度最优为目标,对HVAC系统的运行策略进行优化,为解决模型的耦合问题,对HVAC系统进行双层优化控制,上层优化送风质量流量,下层优化通风率,并采用滚动优化方法修正误差;最后,在夏季制冷场景下,对不同舒适度系数下的双层优化控制结果进行分析,并与其他控制策略进行比较。结果表明,所提方法能兼顾经济性和用户舒适度。

Regional Distribution of Perceived Temperatures Estimated by the Human Heat Budget Model (the Klima-Michel Model) in South Korea

The regional distribution of perceived temperatures （PT） for 28 major weather stations in South Korea during the past 22 years （1983-2004） was investigated by employing a human heat budget model, the Klima-Michel model. The frequencies of a cold stress and a heat load by each region were compared. The sensitivity of PT in terms of the input of synoptic meteorological variables were successfully tested. Seogwipo in Jeju Island appears to be the most comfortable city in Korea. Busan also shows a high frequency in the comfortable PT range. The frequency of the thermal comfort in Seoul is similar to that of Daejeon with a relatively low frequency. In this study, inland cities like Daegu and Daejeon had very hot thermal sensations. Low frequencies of hot thermal sensations appeared in coastal cities （e.g., Busan, Incheon, and Seogwipo）. Most of the 28 stations in Korea exhibited a comfort thermal sensation over 40% in its frequency, except for the mountainous regions. The frequency of a heat load is more frequent than that of a cold stress. There are no cities with very cold thermal sensations. In this study, we found the decreasing trend of mortality with an increasing PT. If the PT is over any critical temperature point, however, the mortality rate increases again. The mortality variation with the PT of a station seems to be associated with the latitudinal location of the station, implying that it results from a regional acclimation effect of inhabitants.

基于用户差异化热舒适度的空调负荷聚合调度策略

空调负荷作为需求侧重要资源,可灵活参与电力系统,促进新能源消纳。在空调负荷调度过程中,不同用户的热舒适要求和调度潜力存在差异。如何满足用户差异化热舒适度,且挖掘其调度潜力是要考虑的难题。针对上述问题,文中首先引进热舒适度模型以综合量化用户的热舒适体验;其次,根据热舒适度模型中的人体参数,采用K-means聚类方法划分出不同热忍受能力特征的用户群体。在此基础上,提出基于用户差异化热舒适度的空调直接负荷控制策略,并对其进行仿真验证。算例分析表明,相较于传统策略,文中所提策略在完成消纳任务的基础上挖掘了每类用户群体的调度潜力,并保障了其热舒适性。