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Indoor thermal climate is an important issue affecting the health and productivity of building occupants. In the designing of commercial air-conditioning systems, it is believed that the conventional fixed temperature set point concept is limited because indoor comfort temperature depends on the business culture, such as the nature of activities and dress code of occupants, etc. Researchers have been interested in investigating adaptive temperature control for a realistic in-situ control of comfort. Unfortunately, those studies put great emphasis on energy saving opportunities and sometimes might result in thermal discomfort to individuals. This study argues that complaints of thermal discomfort from individuals, despite representing only a small portion of the population, should not be ignored and can be used to determine the temperature setting for a population in air-conditioned environment. In particular, findings of a new notion of Bayesian adaptive comfort temperature (BACT) in air-conditioned buildings in a humid and subtropical climate like Hong Kong are reported, and the adaptive interface relationship between occupants’ complaints of thermal discomfort and indoor air temperature is determined. This BACT algorithm is intended to optimise the acceptance of thermal comfort, as determined by physical measurements and subjective surveys.

Shanghai International Gymnastics Stadium is the selected object for site-measurement. The site-measurements have been carried out during summer, winter, and the transitional seasons. Their indoor thermal environments were controlled by continuous air-conditioning, intermittent air-conditioning and natural ventilation, respectively. The site-measurement includes outdoor environment (the weather conditions and peripheral hallway), indoor air temperature distribution (the occupant zone temperature, radial temperature near upper openings and the vertical temperature distributions, etc.), and the heat balance of air-conditioning system, etc. It is found that temperature stratification in winter with air-conditioning is most obvious. The maximum difference of vertical temperature is 15 °C in winter. The second largest one is 12 °C in summer, and less than 2 °C in the transitional season. The results of measurements indicate that it is different in the characteristics on energy saving of upper openings during the different seasons. With heat balance measurements, it is discovered that the roof load and ventilated and infiltrated load account for larger percentages in terms of cooling and heating load. In this paper, many discussions on the results of site measurements show some characteristics and regulations of indoor thermal environment in large space building.

Hybrid fuzzy logic control (FLC) strategies for hot water district heating (HWDH) systems are designed. A non-linear dynamic model of a HWDH system (heated floor area 90 000 m2) with 21 dynamic equations is developed. The dynamic model consists of a boiler, pipe network, heaters and buildings. Six different hybrid control strategies involving FL and PI control were designed to regulate fuel firing rate, water flow rate or water temperature in the system. Simulation results show that the control strategies, based on the use of return water temperature and indoor air temperature predictor (IATP), give good zone temperature control. Pumping costs were reduced by modulating water flow rate in the system. Results also showed that the proposed hybrid control strategies could save up to 17% energy in buildings.

This study investigates and summarises the results of physical measurement of the indoor environmental quality (IEQ) in hospital building wards in Plateau State, Nigeria comparing two hospital settings. The results indicate that the mean indoor air temperature in the case study hospital ward buildings exceeded the range of 23-26oC as recommended by international standards. The temperature levels in the teaching hospital ward buildings were relatively lower than what was obtained in the specialist hospital whose ward buildings lack proper ventilation. The amount of daylight requirement on an average were below 300Lux in the specialist hospital whose façade orientation and window-wall-ratio (WWR) could not allow for maximum sunlight penetration, while it was above 300Lux in the teaching hospital. However, the sound intensity level in both hospital ward buildings ranged between 52.7dBA and 71.3dBA. This study therefore recommend that, hospital building design or retrofitting should employed common strategies towards increasing ventilation and daylight with minimal energy consumption.

This paper proposes an implementation of advanced heating feed-forward control system for multistorey buildings based on indoor air temperature inverse dynamics model. The suggested model structure enables real-time assessment of the impact of unmeasurable perturbing factors on indoor air temperature, along with distinguishing between fast and slow processes occurring within the system. The paper also contains the actual results obtained by deployment of the suggested heating control system in the academic building of South Ural State University. The results obtained demonstrate the reducing of overall energy consumption by building heating system, at the same time increasing the comfort level of the building.

In this article, recent developments on the efficient control of residential indoor thermal environment are reported. Firstly, fundamental issues for indoor environmental control in residences are discussed. This is followed by presenting an analysis of a number of current control issues for direct expansion (DX) air-conditioning (A/C) systems, including the capacity control, humidity control, and the inherent operating characteristics of a DX A/C system. A number of studied efficient control strategies for simultaneous controlling indoor air temperature and humidity using a DX A/C system, including direct digital control (DDC)-based control, multi-input multi-output (MIMO) control, and artificial neural network (ANN)-based control, are reported subsequently. Finally, some other related issues on residential indoor thermal environmental control using DX A/C systems, including a novel indoor humidity control algorithm (H–L (high–low) control algorithm), capacity control of multi-evaporator air-conditioning (MEAC) systems, and A/C for sleeping environments in the tropics and subtropics are discussed. It is expected that with the improvement on indoor thermal environmental control in residences, occupants' thermal comfort can be improved and more importantly, the energy use for A/C residential buildings reduced. This would in turn help reduce energy consumption in buildings, and thus carbon emission, contributing to sustainable development. Keywords: indoor thermal control; residential buildings; energy efficient; dehumidification

The paper gives an overview of indoor climate studies in various schools in Estonia. It is based on various measurements of indoor air temperature and CO2 concentration in six different schools and provides an overview of the principle of determining the CO2 level. The indoor climate in six school buildings was investigated and students’ relative performance was determined. The study showed that indoor air temperature in the classes of the studied schools is at a satisfactory level. At the same time even in renovated schools, there are problems with air quality (the CO2 level is usually very high and air change is modest). The outcome is low learning performance. Because the ventilation in classrooms is modest, students’ relative performance is not high. This study shows that well-organized ventilation in classrooms is important, not only from the aspect of indoor climate comfort, but also significantly affects students’ performance. To improve this situation it is necessary to raise the quality of renovation and the operational level of HVAC systems.

Assessing the effectiveness of energy conservation measures (ECMs) prior to their actual implementation in buildings is critical. There is an increasing tendency to employ calibrated building energy models to quantify energy savings that could be achieved by ECMs to justify their implementation. However, there is empirical evidence that reveals noticeable discrepancies between simulated and measured performances of ECMs in buildings. One possible reason for such discrepancies is that actual building occupancy, which is a critical factor that determines the total and peak loads of building systems and related energy consumption, is not represented accurately in most energy models. This paper specifically examines the impact of actual building occupancy on the assessment of ECMs. Two energy models of an office building were built and calibrated with the same audit data following the same procedure, except that one used assumed occupancy and the other used actual occupancy. Both models were used to assess an ECM, which adjusts indoor air temperature set points based on the time of the day. Statistically significant differences were observed in the energy consumptions reported by the two models through paired t-tests. The results highlighted the importance of integrating actual occupancy in the assessment of ECMs.

The direct expansion (DX) air conditioning (A/C) system has been widely used to control indoor air quality (IAQ) and maintain thermal comfort simultaneously. Generally, conventional controls for IAQ are designed by using on/off control or proportional integral (PI) control. In this paper, a model predictive control (MPC) is proposed to guarantee thermal comfort and indoor air quality. The DX A/C plant is modeled into a nonlinear system, with speed of compressor and supply fan being regarded as control inputs. To facilitate MPC design, the nonlinear model is linearized around its working point. The proposed MPC is designed based on the linearized model. Simulation results indicate that, by using the proposed MPC, the indoor air temperature and humidity could achieve their comfort levels simultaneously.

One crucial aspect in building engineering is to accomplish the trade-off between reduction of energy consumption and high level thermal comfort for the occupants. To this aim, advanced control algorithms are fundamental to guarantee a certain optimality of the system performance in working conditions that can be quite different from the nominal ones due to the presence, for example, of variable external wheatear conditions or parameter uncertainties. To impose an optimal behavior of the indoor air temperature while assuring robustness to plant parameter uncertainties and external disturbances, in this paper we propose an extension of the optimal model reference adaptive scheme presented in [6] that embeds additional adaptive actions to improve tracking performance. Performance of the novel strategy are investigated both analytically, by exploiting hyperstability theory, and numerically. In particular the numerical validation has been carried out by using a detailed thermal-hygrometric simulation code (DETEC 2.1). Results confirm the effectiveness of the control in exemplar case of studies referred to buildings of different sizes and located in different European weather zones.

Under the circumstances of backward production tools and technologies, varied and graceful local buildings are built by using the local materials with the wisdom of the working people. The article analyzed stone dwellings in Yuhu village in Lijiang Yunnan Province as cases. Based on the field testing and analysis of the stone dwelling in Lijiang , and more specifically, the indoor temperature of the dwellings with stone walls as well as the surface temperature of building envelope were tested and comparatively analyzed. The test results reveal that the maximum and the minimum of the indoor air temperature is 5.1℃ and 8.4 ℃ higher than one of the outdoor temperature, an amplitude of the indoor air temperature is 3.6℃ lower than one of the outdoor temperature. The test results show the current situations and features of indoor temperature changes of these dwellings of stone materials, the heat-insulation performance and heat stability of stone wall, which may provide a basis for improving the thermal environment of Naxi nationality dwellings.

Based on experimental data, the energy storage performances of floor radiant heating system were investigated. The decrease of indoor air temperature after the stopping of floor heating was compared with that of fan-coil heating system. The increase of indoor air temperature after the stopping of floor cooling system was analyzed. The results show that the floor heating system has good thermal storage performance, which can be used to a night-running model to obtain the energy-saving benefits efficient and economic running cost, and still can be used for “shifting peak load to off-peak” macroscopically.

In Spain there is a great heritage of traditional underground wine cellars. Since the depth of these cellars in the studied area is from 1 to 6 m, the thermal inertia is very high which causes the indoor air temperature to follow the outdoor temperature with a great attenuation and time lag. There is a simply and well-known analytical model to predict soil temperatures. In this article the potential of this analytical model to predict the temperature inside the wine cellars is analyzed. The result shows that by changing the average annual ground temperature, the model and the experimental are in good agreement. The model is worth to predict the indoor temperature range but it is not good to predict the indoor temperature course.

The design of residential buildings has a significant impact on people's daily life. The ‘terrace house’ form constitutes the majority of the residential building stock in Malaysia. The lack of thermal comfort in terrace houses is mainly due to the poor thermal properties of the building materials and to design factors [1]. The evaluation is derived from a series of computer simulations using commercially available software. This paper concentrates on analysing the effect of the orientation of the existing case of a typical terrace house in Malaysia by finding the dynamic indoor air temperature for each orientation. Copyright , Manchester University Press.

Vaulted or domed roofs have been frequently adopted by builders and architects throughout the Middle East and other hot dry areas. However, the thermal performance of such buildings under hot dry climatic conditions has rarely been quantitatively studied. In this paper, a detailed finite element model for the investigation of the thermal performance of non air-conditioned buildings with vaulted roofs (VR) is suggested based on two-dimensional unsteady heat transfer in such roofs and solar geometry. This model allows a comparison of the thermal performance of non air-conditioned buildings with a VR and a flat roof (FR) under different climatic conditions. Results obtained by numerical calculation show that, irrespective of building type the VRs are applied to, buildings with a VR have lower indoor temperatures as compared to those with a FR. The reason is that such roofs dissipate more heat than a FR does by convection and thermal radiation at night due to the enlarged curved surfaces. This implies that such roof forms are suitable for buildings located in hot dry regions but not for those located in hot humid areas, and reasonably explains why curved roofs have been extensively adopted by builders and architects in the hot dry areas in the past. However, with the decrease in the half rim angle of a VR, the difference of indoor thermal condition between a VR and a FR building becomes small and insignificant. Results also indicate that the indoor air temperature is slightly influenced by the half rim angle θ 0 and the orientation φ v of the VR. To be effective to create a favorable thermal condition inside buildings with a VR under hot dry climatic conditions, the half rim angle of a VR should be θ0>50°, instead of θ 0 5 0 ∘ , which is the optimal half rim angle of a VR of air-conditioned buildings, as found by the present authors in a previous study.

Conservation of ancient buildings is a major issue for modern societies, both from economical and cultural viewpoints. Information about the ancient built heritage is vital to plan adequate remedial measures. Using a historic centre in Portugal as a case study, this paper presents an extensive survey of building typology and materials, damage in the building envelope, indoor survey of damage, and measurements in indoor air temperature and relative humidity. Water-related problems can be confirmed as the single most important defect, which are combined with inadequate sun exposure, ventilation and heating, and excessive moisture indoor production. Extremely low temperatures, high humidity and presence of mould therefore compromise the indoor quality of life of the inhabitants, being urgent repair needed at many levels.

Because variable air volume (VAV) air conditioning system has the feature of intense coupling among multi-loops, supply air temperature cannot follow the set-point value closely. Therefore, the precision and performance of indoor air temperature of VAV air conditioning system is influenced. In this paper, precision and performance of indoor air temperature of VAV system are highly improved through state feedback decoupling and genetic algorithm. The coupling between loop of supply air temperature and loop of indoor air temperature is eliminated in the method of state feedback decoupling. Besides, the controller parameters are optimized by means of inverse and genetic algorithm. LonWorks technology is adopted in VAV air-conditioning decoupling control system so that data can be exchanged among multi-loops. The experimental results show that performance of indoor air temperature of VAV system is improved effectively.

Two distinct groups of individuals (staff and patients) occupy hospital environments. The physical, social and individual needs of the patients as well as of the nursing staff vary to a large extent. Consequently, it is important to provide for a comfortable indoor environment for both groups of individuals. The variations between the groups make it hard to optimize the indoor environment for all individuals. Objective measurements and distribution of questionnaires were administrated in an orthopaedic ward. Questionnaires were distributed in order to learn more about how the indoor environment is perceived. To assess the response to the questionnaires, physical indoor climate variables were measured simultaneously. A combination of objective measurements and questionnaires is a suitable method to assess and analyse the indoor environment in hospital buildings. The data was collected during summer and winter to in order to identify possible seasonal variations. Comparisons show that the difference between staff and patients perception of the indoor air temperature differ more during winter than summer despite that physical measurements showed that the temperatures were similar in both seasons.

Studies, around the world, have demonstrated that envelope colour has significant effect on building thermal performance and the use of thermal mass can usefully modify the thermo-physical signature of buildings. However, their influences under hot-humid climate have not been investigated in details. In view of the issue, a testing facility has been established in the Department of Architecture of the Chinese University of Hong Kong; the facility allows study of the effect of various building design features on indoor temperatures. This paper presents the results of investigation about the effect of envelope colour and thermal mass on indoor temperatures. The study reveals that the use of lighter surface colour and thermal mass can dramatically reduce maximum indoor temperatures. However, their applications in building design could be very different, and to a large extent, depend on the circumstance. Furthermore, the paper demonstrates the possibility to develop predictive formulas for daily maximum indoor air temperature.

【Draft is defined as an unwanted local cooling of the human body caused by air movement. It is a serious problem in many ventilated or air conditioned buildings. Often draft complaints occur although measured velocities in the occupied zone maybe lower than prescribed in existing standards. Purpose of this study is to clarify the evaluation of thermal comfort based on temperature and air velocity in winter. Experiments were performed in an environmental chamber in winter. Indoor temperature and air velocity was artificially controlled. The experiments were performed to evaluate temperature conditions and air velocity conditions by physiological and psychological responses of human. According to physiological responses and psychological responses, it was clear that the optimum air velocity is about 0.15 m/s and 0.30 m/s.】

In this work, low temperature geothermal district heating systems with heat pumps have been studied and compared with fuel-oil boiler heating systems for intermittent and continuous regimes according to the optimum indoor air temperature and operational cost. Izmir Institute of Technology (IZTECH) Campus is taken as a case study. Various heat pump and boiler configurations are studied to meet required duty. Operational cost analysis for each alternative is conducted. According to the results, for IZTECH Campus the best alternative, which gives the optimum indoor air temperature and the lowest operational cost, is heat pump continuous regime.

Commenting on some negative effects of traditional conditioning strategies of indoor thermal environment in warm climates, the authors present a fundamental concept of thermal comfort and acceptability, new air-conditioning strategies by using fluctuating air movement based on the findings of human responses to transient thermal environment, and a prediction of energy saving caused by elevated indoor temperature settings. In addition, how to meet the requirement of providing human-beings a healthy, comfortable and affordable indoor air temperature, and to achieve a goal of sustainable development are also discussed in this paper.

In the article a verification of indoor climate requirements for Russian churches and cathedrals and recommendations on maintenance are given. From the point of view of building physics and longevity of building materials, frescos, icons, wood, paper, leather, parchment and natural textiles are regarded as capillary-porous physical bodies partly filled with moisture which includes dissolved salts. Porosity can be divided into three groups: large, moderate and small. What happens with these physical bodies when the indoor temperature and humidity changes is that deformation occurs and this may lead to breakage. Research to determine the dependence of deformation on the humidity of the surrounding structural materials of the cathedrals was carried out by a holographic interferometer. Diagrams of humidity and temperature deformation show the following results: the graphics of humidity and temperature are alike, the temperature deformations are not extensive, deformation due to humidity is more serious than deformation caused by temperature. The investigations of temperature and humidity deformation made it possible to give recommendations for the level of indoor air temperature and humidity in cathedrals. On the basis of these investigations, the Russian standard "Orthodox temples. Heating, ventilation, air conditioning" was developed (ABOK, 2002).Temperature and humidity changes can affect building materials and the building structure. In the case of Russian cathedrals and churches, traditional artefacts are also affected.

We developed a neural network model describing the process in which disturbance conditions, such as outdoor air temperature, and activity conditions, such as indoor air temperature and humidity, affected the chilled water thermal quantity for HVAC systems in a commercial building in the city of Kitakyushu, Japan within three years after its completion. The influence of each of the disturbance conditions and the activity conditions, which changed every year, on the chilled water thermal quantity was diagnosed quantitatively by a numerical simulation using these models, and how to macroscopically evaluate the carried-out energy-saving activity was shown.

In this study, a detailed simulation model is developed for the investigation and analysis of a roof pond with gunny bags (RPWGB) floating on the water surface which was suggested and experimentally investigated in a previous study of the present authors. The model is based on the newly proposed empirical correlation of water evaporation rate from a wetted surface to the ambient air proposed by the present authors, and takes into account the response of buildings as a whole to evaporative cooling. Results by simulations show that, regardless of the type of buildings the technique is applied to, RPWGB has a better cooling performance in terms of the indoor air temperature and heat flux through the roof into pond as compared to a roof covered with wetted gunny bags, which had been widely considered to be one of the most efficient roof cooling techniques. The reason for its higher efficiency is the thermal stratification inside the pond. The simulated results also reveal that the optimal water depth in the RPWGB depends on the roof type in general, and it is about 20 cm for a concrete roof and is about 5 cm for metal-decked roofs.

Seven schools in Lower Saxony participated in a scientific research project measuring the concentration of carbon dioxide (CO 2 ), indoor air temperatures and the relative air humidity in naturally ventilated classrooms on 58 days during the period of one year. The results are as follows: - The hygienic reference value of 1500 ppm CO 2 (in accordance with the official German regulation DIN 1946-2) was exceeded on 7 days in summer when measurements were taken (32% of all samples in summer) and on 32 days in winter (89% of all samples in winter). - The mean CO 2 -concentration was 1316 ppm, 766 ppm and 1652 ppm in all samples (58 measuring days), summer samples (22 measuring days) and winter samples (36 measuring days), respectively. The mean indoor air temperature was 21.7°C, 22.9°C and 20.9 C. The mean relative humidity was 50.7%, 54.3% and 48.5%. - The mean number of persons per classroom (including the teacher) was 25.1, corresponding to a mean volume of 8.5 m 3 for each person and a mean area of 2.9 m 2 per person. - A statistical association of CO 2 concentration with season, outdoor temperature and the age of the windows was found. - A software programme has been developed for calculating the concentration of CO 2 depending on the number of persons and the ventilation rate in a classroom. - A 3-level scheme based on CO 2 concentration was developed to assess the air quality. The results showed that the classrooms were not ventilated regularly but depending on the outdoor temperature and the season. Deficits concerning all 3 parameters were found. It is very likely that the deficits are not limited to the schools participating in this project. Ventilation and indoor climate deficits might cause health problems and therefore lead to costly measurement programmes. To enable schools to take their own health-related measurements, measuring instruments were purchased which can be loaned to schools in Lower Saxony.

This paper presents a detailed analysis of the measured data on the indoor air of an historical building: tezone 105 of the Arsenale in Venice. During one year of measurements, the indoor air temperature and the air humidity have been collected: the probes have been placed in different sites in order to provide total control of the microclimate. The status of the internal walls has been checked by means of the measurement of the surface temperatures by different sets of thermal resistances. The data collected point out the water wall imbibition and the high thermal capacity of the building envelope. The collected information could be used for the design of the thermal system.

Recent studies show that the relative humidity and the indoor air temperature constitute an important determinant of the quality of indoor air. Hygrothermal microclimate has a significant impact on occupant's health and their comfort. The study presents the results of experimental measurement of indoor air temperature and relative humidity in selected apartment in prefabricated panel house situated in Ostrava, Czechia. The contribution describes and analysis the relation between indoor air temperature [°C] and relative humidity [%] in this apartment. The experimental object is selected with respect to the housing stock in the Czech Republic. A third of the housing stock in the Czech Republic is composed of prefabricated panel houses. Regeneration and revitalization of these buildings were in the focus of interest during recent years. Building modifications, such as thermal insulation of building envelope or window replacement, lead to a significantly higher level of airtightness of these objects. Humidity and indoor air temperature are measured in 10-minute cycles for two periods. The values of temperature and humidity are measured for the non-heating and the heating season. The length of each experimental period is 30 days. The mean value of indoor air temperature is 22.21 °C and average relative humidity is 45.87% in the non-heating period. The values of 22.62 °C and 35.20% represent average values for the heating period. A slight increase of the average temperature of the indoor environment (+1.85%) is observed. The decrease of the relative humidity is evident at first glance. The relative humidity of the internal environment is approximately 10% lower in the heating period. Long-term decline of relative humidity below 30% brings many problems. It is necessary to take measures to increase of relative humidity in residential prefabricated building. The aquarium appears to be ineffective. The solution may be forced artificial ventilation or humidifiers.

The contribution presents results of the experimental measurement of indoor air quality in residential prefabricated buildings. People spend about 90% of their life in the indoor environment of buildings. Hygrothermal parameters and indoor air quality are the essential component that define the quality of the indoor environment. The results of case study characterize the quality of the indoor environment of the ordinary occupants in housing unit of residential prefabricated building. A current problem of revitalized prefabricated buildings is inadequate air exchange and related thereto to poor indoor air quality. The experimental measurements were carried out just before and at the beginning of the heating season (from 1st October to 30th November 2016). Heating season was launched in the middle of experimental measurement. The wireless indoor sensor Elgato Eve Room was used for measurements. The obtained values of indoor air temperature [C], relative humidity [%] and indoor air quality [ppm] are describe and analysis in this study. The results of the study indicate that the values of temperature and indoor air quality meet optimal levels during the experiment with nuances. The mean air temperature in the indoor environment is 22.43 C. The temperature of the indoor environment is held at the optimum level (18-24 C) for 94.50% time of the experimental measurements. In addition, the indoor air quality in the context of the content of harmful volatile organic compounds (VOCs) has been excellent for almost 91% time of the total experiment. However, the values of relative humidity were less than the optimum value nearly 40% of the total observed time. The mean 10-minutes values of relative humidity during the heating season is about 10% lower than the mean 10-minutes relative humidity before the heating season.

After sunset, the indoor of buildings would be relatively warmer as compared to that of the outdoor due to thermal was associated with the heat stored in the building structures and furniture. In tropical countries, doors and windows are usually shut after sunset in order to avoid mosquitoes. Thus, the condition of the indoor air is worsened as the hot air is trapped inside the bedroom and takes long time to be fully dissipated to the surrounding. This causes discomfort to the occupants as bedrooms where they are expecting to have a good rest to rejuvenate from hard day works. The objective of this study was to analyze the nature of air temperature profile in bedrooms of a hostel at night and the effect of ventilation systems in reducing the indoor air temperature. The study was conducted by measuring temperature of air in the bedrooms throughout a night. It was found that the exhaust fan gave the best results by reducing the air temperature by 1.5°C to 2.5°C.

Now requirements for the thermal performance of building walls are based on the assumption that heat flux transfers in one direction through the wall. However, in Hot Summer and Cold Winter Region of China, the direction of heat flow in the wall not only changes with the seasons, but also changes in the same period of using. In this paper, dynamic thermal process of externally insulated walls in different air-conditioner’s running state in summer in Chongqing, China, was tested. The distribution characteristics of the outdoor and indoor air temperature and the surface and inner temperatures of the wall were analyzed and demonstrated. Based on the unsteady-state heat transfer theory, the study calculated and analyzed the distribution characteristics of the direction of the heat flux in the thermal process. Also the characteristics of insulation and heat preservation for walls under different air-conditioner’s running state were analyzed. It is shown that, in any air-conditioner’s running state, the direction of the heat flux through the wall is obviously dynamically changing. There is obvious difference in the thermal performance needs of the wall; that is, it has strong demand for thermal insulation in daytime and strong demand for heat dissipation during night time in summer.

Summary Gartner who had been called to the first Chair of Hygiene in Jena in 1886 has provided impulses decisive for the development of hygiene in the fields of construction, housing and communities. He has formulated important requirements for indoor climate, e. g. for heating, ventilation, indoor air temperature, indoor air humidity, avoidance of temperature asymmetry and thermal insulation of houses. His requirements to ensure adequate insulation, e. g. a ratio between window area and floor area of 1:8-1:10, have remained valid until today. Missing attention to his findings with regard to sewage disposal gained on the occasions of two typhoid outbreaks in Jena as early as in 1901 and 1915 resulted in the last water-borne typhoid outbreak in Germany in 1980, in the same place.

The objective of this research is to investigate thermal comfort and air flow distribution inside a test room that is naturally ventilated. The test room is situated in a relatively sheltered location and is ventilated through adjustable louvres. The air pressures and velocities across the openings together with indoor air temperature and velocity at four locations and six different levels are measured. The outside local temperature, wind velocity and direction are also monitored. The collected data are used to predict thermal comfort parameters across the test room. Tests were carried out over winter and summer times. The experimental results demonstrate that for both winter and summer the air was entering the test room at the bottom and leaving at the top louvre. The amount of air flow over the winter was increased as the heat input varied from 2 kW to 4 kW. The predicted thermal comfort indicated that PPD values (percentage of people dissatisfied) for summer are significantly improved with a higher temperature difference between inside and outside and higher wind velocity. Over the winter period with internal heat load of 4 kW the PPD values were improved by 40%.

SYNOPSIS This study reports an experiment to investigate the feasibility of a passive heating roof-pond system on an existing room in the cold winter conditions of Riyadh, Saudi Arabia. Statistical analyses of data recorded during the winter season of 1996–97, are carried out to evaluate the thermal peformance of the proposed system. Total effective heating and the heating power of the roof pond system are computed and analysed. Results indicate that the roof-pond system is capable of maintaining warm indoor air temperature conditions. The statistical formulae for this system are presented and used to estimate the indoor daily average air Dry Bulb Temperature (DBTAvg-indoor] created by the system. Validation of the proposed formulae is also presented.

This paper presents the results of ambient and indoor air temperature measurements in the dwellings of Solar Village-3, Athens. The temperatures were monitored centrally using a Data Acquisition System and the measurements cover a 37 continuous month period, from 1/12/88 to 31/12/91. The main effort in this paper was given to the appropriate elaboration and presentation of indoor air temperature measurements in all buildings of Solar Village-3 for all the evaluation period as well as detailed data for representative dwellings. The elaborated data are average, maximum and minimum daily values for buildings, apartments and rooms, as well as daily variation of half hourly values. The daily average temperatures of each apartment are weighted average of the daily mean temperatures of each room, which in turn is the mean value of 48 measurements/day (every 30 min). Analysis shows that indoor temperatures measured during the evaluation period contributed to prevail thermal comfort conditions in winter as well in summer days. Analysis also shows that buildings of high thermal capacity and proper insulation have no need for air conditioning.

An extensive literature review of research on the impact of indoor air conditions; temperature, relative humidity and surface air velocity on materials emission rates is presented. This paper also presents the results of an experimental work to study the impact of room air temperature and relative humidity on materials emission rates. The results indicate that both the temperature and relative humidity have a significant effect on the emissions from paint and varnish. In the case of varnish, the results were consistent with earlier results. However, the paint results show inconsistent emission behaviour. Further, for both materials, the individual compounds did not necessarily follow the same trend established for the TVOC.

The airflow distribution inside a naturally ventilated lightweight test room is investigated. The room is situated in a relatively sheltered location and is ventilated through adjustable louvres. Indoor air temperature and velocity are measured at four locations and at six different levels for various sizes of opening. The outside local temperature, wind velocity and direction are also monitored. The collected data are used to predict thermal comfort parameters across the test room. The experimental results demonstrate that a displacement mode of ventilation is maintained in the space when the wind comes from behind the test room. When the wind impinges on the louvre bulkhead the displacement flow into the room is reduced. Predicted mean votes (PMV) for thermal comfort indicate that values in the afternoon are significantly improved with a higher internal air velocity.

From August 1993 to December 1995 a survey of the temperature and moisture conditions was carried out in 329 livestock buildings in Northern Europe. Mean, standard deviation, minimum and maximum values of dry bulb air temperature and relative humidity (RH) in cattle, pig and poultry houses were measured over 24 h in each building. Indoor air temperature and RH were generally in agreement with recommended values with few adverse consequences for health or production. Nevertheless, high air temperatures occurred occasionally in summer, indicating the limits of control of temperature in mechanically ventilated buildings. Naturally ventilated houses were more influenced by the prevailing climate.

We have suggested a complexity measure based method for studying the dependence of measured 222Rn concentration time series on indoor air temperature and humidity. This method is based on the Kolmogorov complexity (KL). We have introduced (i) the sequence of the KL, (ii) the Kolmogorov complexity highest value in the sequence (KLM) and (iii) the KL of the product of time series. The noticed loss of the KLM complexity of 222Rn concentration time series can be attributed to the indoor air humidity that keeps the radon daughters in air., 20 pages, 4 figures; This paper has been submitted to Applied Radiation and Isotopes

In this paper, we focus on the effect of partition setting between enclosed balcony and its directly connected room. In residential buildings, the heat lose through balcony components makes disadvantage for energy saving. In order to avoid these adverse effects of enclosed balcony, Design Standard for Energy Efficiency of Residential Buildings in Severe Cold and Cold Zones rules that partition should be set between enclosed balcony and its directly connected room; if there is no partition, the heat transfer coefficients of the enclosed balcony envelope, as well as window to wall ratio, should be controlled within a reasonable range. To evaluate the effect of balcony partition, we use DeST-h software to simulate these two situation—balcony with partition and without partition. According to the simulation results, we come to such a conclusion that the heating load of the room with balcony partition is lower than that without, and the outside surface of balcony should be set with insulation.

The low-temperature hot-water floor radiant heating system could intermittently work without impacting the indoor thermal comfort conditions for occupants. According to the urban resident life work and rest mode and the change characteristics of indoor air temperature caused by intermittent operation of this system, the control strategies of the system of the urban residential building were proposed. The control strategies contained the average temperature adjustment of coil supply and return water and the time adjustment of system start/stop. In the different control strategies, the indoor air temperatures of the south room and the north room were analyzed by numerical simulation. The results indicated that to meet the thermal comfort requirements for most occupants, the north room needed to be heated about 18 h per day, while the south room only needed to be heated for 13–14 h per day.

In order to investigate indoor thermal environment and thermal comfort at rural houses, a field study was carried out at 10 rural houses in 2 villages near Harbin from December 2012 to January 2013. The environmental parameters and the subjects’ thermal sensation were collected simultaneously. The results showed that the indoor air temperature ranged from 9.0 to 21.8 °C, with an average of 16.6 °C. The operative temperature varied within the range of 10.5–22.7 °C, averaging 18.1 °C. The average relative humidity was 40.4 %. The mean air velocity was 0.08 m/s. The mean surface temperature of Chinese Kang was 35.1 °C. The mean surface temperature of exterior window was 9.5 °C. The neutral operative temperature was 18.5 °C. The lower limit of the accepted operative temperature by 80 % of the peasants was 10.6 °C, much lower than the specified heating temperature for urban residential buildings, because the peasants wore more clothes than residents in the urban. The mean clothing insulation was 1.47clo. 92.5 % of the subjects felt the thermal environment acceptable, and 92.5 % of the subjects felt the humidity of the environment acceptable. Regulating the Kang and the separated heating equipments were the main measures taken by the occupants to improve the indoor environment.

Maintaining good indoor air quality (IAQ) aimed at meeting human requirements on health and comfort of a space. This study takes the IAQ of the construction square of Xi’an University of Architecture and Technology before winter heating as an example. Four basic parameters: indoor air temperature, CO2 concentration, relative humidity and wind speed were tested to evaluate the basic condition of IAQ in the construction square. Through the analysis of the basic parameters of indoor air changes with time and the influence to the human body, this study will point out the existing problems in this space and give some improving suggestions.

Indoor air temperature, floor temperature, and wall surface temperature were measured when lightweight radiant floor cooling combined with underfloor ventilation (LRFCUV) air conditioning system and heavy radiant floor cooling combined with underfloor ventilation (HRFCUV) air conditioning system operated. And indoor air temperature field, heat-transfer capability, and thermal comfort were analyzed. Experimental results show that LRFCUV air conditioning system started up faster than HRFCUV air conditioning system. When the system reached stable condition, net radiant floor heat quantity of HRFCUV air conditioning system was larger than that of LRFCUV air conditioning system, and thermal comfort of HRFCUV air conditioning system was better than that of LRFCUV air conditioning system.

This paper studied the effect of the combined operating of radiant floor and fresh air coil in field experiment according to different ways of cold or hot water supply. By compared and analyzed the differences, which among indoor air temperature/humidity, radiation asymmetry, and thermal comfort in three ways of single, series, and parallel of radiant floor and fresh air coil for cold or hot water. On the basis of the analysis, this paper also discussed the risk of condensation on the surface of the floor. Experimental results showed that the indoor thermal comfort is best and the risk of floor surface condensation is least in series mode.

Present relief camp built with lightweight envelope has obvious cold-house effect and poor indoor thermal environment. Advantage of phase change material provides one possible way to improve thermal performance of lightweight envelope. This study analyzed the thermal performance of lightweight envelope with and without PCM and presented their difference by establishing one experimental system, including one special model with PCM and one ordinary model without PCM. The results show that the lightweight envelope integrated with PCM has better thermal performance and thermal inertia than those of lightweight envelope without PCM. Meanwhile, PCM applied in lightweight envelope can make indoor air temperature fluctuation be weak. This study provides some guides for structure design and optimization of relief camp, in order to acquiring favorable indoor thermal environment.