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Thermal comfort is increasingly recognized as vital in healthcare facilities, where patients spend 80–90% of their time indoors. Sensing, controlling, and predicting indoor air quality should be monitored for thermal comfort. This study examines the effects of ventilation design on thermal comfort in hospital rooms, proposing four distinct ventilation configurations, each with three airflow rates of 9, 12, and 15 Air Changes per Hour (ACH). The study conducted various ventilation simulation scenarios for a hospital room. The objective is to determine the effect of airflow and the diffuser location distribution on thermal comfort. The Reynolds-Averaged Navier–Stokes (RANS) equations, along with the k–ε turbulence model, were used as the underlying mathematical representation for the airflow. The boundary conditions for the simulations were derived from the ventilation standards set by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) and insights from previous studies. Thermal comfort and temperature distribution were assessed using indices like Predicted Percentage Dissatisfaction (PPD), Predicted Mean Vote (PMV), and Air Diffusion Performance Index (ADPI). Although most of the twelve scenarios failed to attain thermal comfort, two of those instances were optimal in this simulation. Those instances involved the return diffuser behind the patient and airflow of 9 ACH, the minimum recommended by previous studies. It should be noted that the ADPI remained unmet in these cases, revealing complexities in achieving ideal thermal conditions in healthcare environments. This study extends the insights from our prior research, advancing our understanding of ventilation impacts on thermal comfort in healthcare facilities. It underscores the need for comprehensive approaches to environmental control, setting the stage for future research to refine these findings further. [ABSTRACT FROM AUTHOR]

The indoor air quality is one of the main factors that influence the thermal confort and, consenquently, the human performance inside buildings. Throughout the years, a lot of studies described the relation between the climate confort and the performance .This study follows the thermal sensations of students in a seminar room during the summer and winter periods and presents the results between them. [ABSTRACT FROM AUTHOR]

The European regulations are demanding more than ever to reduce the energy consumption for buildings and at the same time to raise the Indoor Environmental Quality to a higher standard. This challenge implies that the occupants inside the building should benefit from at least the same thermal comfort conditions at a lower energetical cost. The purpose of this research is to improve the performance of the air diffusers ventilation devices with the purpose of obtaining a more efficient mixing of the airflow from the air diffuser towards the ambient air. In this regard, an innovative cross shaped orifices perforated panel is analysed and compared to a regular panel with circular orifices. The experimental approach was carried out in a climatic chamber. The indoor thermal comfort was assessed at the same time by means of two different experimental devices, namely a thermal manikin and Comfort Sense equipment. The equivalent temperature was assess using the thermal manikin. The panels were also evaluated from the noise levels and pressure losses points of view. By evaluating the PMV and PPD thermal comfort indexes, the results highlighted a more comfortable ambience for a specific person in the room for the cross shaped lobed perforated panel in comparison to the circular shaped perforated panel. Furthermore, it seems that the special geometry of the lobed perforated panel does not generate supplementary noise. The pressure losses of the airflow through the perforated panels were reduced as well.

Thermal comfort is an important element in students' learning activities. The object chosen was the classroom of the Sawah Besar 01 Public Elementary School in Semarang, Indonesia built in a densely populated area, resulting in a window design that has varying orientation directions but with a homogenous façade design. This affects the level of thermal comfort in the classroom. Data analysis was carried out quantitatively - namely, to obtain a thermal comfort index, PMV, and PPD according to the Indonesia National Standard and ASHRAE. The thermal comfort conditions of all selected rooms on the 1st and 2nd floors, either indoor or outdoor, did not meet the comfortable thermal comfort standard for classrooms. The PMV index is above +1 and is mostly categorized as slightly warm, warm, and hot, and all of the PPD percentages are above 10%, indicating that most of the occupants are not satisfied with the temperature in the classroom. New façade opening designs and mechanical ventilation aids need to be applied to improve thermal comfort according to the Indonesia National Standard and ASHRAE. [ABSTRACT FROM AUTHOR]

Human performance and health are among the most relevant topics in modern society, especially at young ages, when academic performance is indispensable. Thus, as humans spend most of their life inside a building, thermal comfort and indoor air quality are essential aspects of a room. The aim of the current study is to numerically evaluate the main thermal comfort parameters such as PMV and PPD as well as indoor air quality, i.e., CO2 concentration, in library group study rooms at the University of Gävle in Sweden. Rotroninc Measurement Solutions CL11 sensors were utilized for temperature measurements. Simulation models were created and validated based on building data as well as temperature measurements. Several simulations were conducted throughout the year, covering different periods. The results show that even though the ventilation system, with only temperature control, works as intended for maintaining thermal comfort, the CO2 concentration rises above 1000 ppm when more than one student occupies the rooms, which is not recommended by different thermal comfort ruling institutions. Consequently, a modification to the ventilation system control is recommended, changing it from temperature control to CO2 and temperature control. [ABSTRACT FROM AUTHOR]

Thermal comfort is increasingly recognized as vital in healthcare facilities, where patients spend 80–90% of their time indoors. Sensing, controlling, and predicting indoor air quality should be monitored for thermal comfort. This study examines the effects of ventilation design on thermal comfort in hospital rooms, proposing four distinct ventilation configurations, each with three airflow rates of 9, 12, and 15 Air Changes per Hour (ACH). The study conducted various ventilation simulation scenarios for a hospital room. The objective is to determine the effect of airflow and the diffuser location distribution on thermal comfort. The Reynolds-Averaged Navier–Stokes (RANS) equations, along with the k–ε turbulence model, were used as the underlying mathematical representation for the airflow. The boundary conditions for the simulations were derived from the ventilation standards set by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) and insights from previous studies. Thermal comfort and temperature distribution were assessed using indices like Predicted Percentage Dissatisfaction (PPD), Predicted Mean Vote (PMV), and Air Diffusion Performance Index (ADPI). Although most of the twelve scenarios failed to attain thermal comfort, two of those instances were optimal in this simulation. Those instances involved the return diffuser behind the patient and airflow of 9 ACH, the minimum recommended by previous studies. It should be noted that the ADPI remained unmet in these cases, revealing complexities in achieving ideal thermal conditions in healthcare environments. This study extends the insights from our prior research, advancing our understanding of ventilation impacts on thermal comfort in healthcare facilities. It underscores the need for comprehensive approaches to environmental control, setting the stage for future research to refine these findings further.

Almost all commuter trains in Japan are equipped with cross-flow fans in order to circulate the air in a cabin and provide beneficial cooling to passengers, especially during the hot and humid summer seasons. The purpose of this study is to propose a method for predicting the passengers’ thermal comfort in non-steady state thermal environments with airflow from cross-flow fans in commuter trains in summer. The proposed method is composed of two calculation parts: a part for calculating sensory temperature based on a human thermoregulation model applicable to non-steady state thermal environments, and a part for calculating the percentage of passengers dissatisfied with the thermal environment based on a statistical model derived from the results of experiments conducted in commuter trains in summer. In order to evaluate the thermal comfort with a cyclic wind from cross-flow fans, the proposed method converts the cyclic wind to a constant wind speed equal to the total amount of heat loss from the whole-body calculated by human thermoregulation model. Applying the proposed method to our previous research where fan-off/fan-on conditions and the congestion rates of below 100%, 120% and 180% had been performed, we examined the prediction accuracy of it. As a result, the mean absolute prediction errors of the proposed method in the congestion rates of below 100%, 120% and 180% under fan-off condition were 9.4pt, 8.2pt and 7.3pt, respectively, and those under fan-on condition were 4.5pt, 10.0pt and 13.2pt, respectively.

The construction industry's excessive energy usage necessitates practical solutions to address this pressing issue. Windows are crucial architectural elements as they allow the majority of natural light to enter a structure. The poorly designed window and related components cause the space to overheat, consuming more energy. However, it negatively impacts the building's thermal and visual comfort. The paper introduces a novel approach for optimizing control parameters for egg shadings through multi-objective methods. The recommended approach significantly reduces the building's energy consumption and enhances its thermal and visual comfort. EnergyPlus is a software utilized for conducting energy-related simulations. The JEPLUS software has therefore considered seven design variables, such as differences in the vertical and horizontal angles of the shade, length and horizontal dimensions, depth and vertical dimensions, and window positioning. These year-round simulations are performed in four different orientations for four different Iranian towns with various climates. The data is improved by using the program JEPLUS + EA. To find the best locations on the Pareto front, the data is optimized using the NSGA-II approach. The optimization results indicate that a lower angle improves visual comfort but takes more electricity for lighting. The findings of multi-objective optimization of controlled blind characteristics improved thermal and visual comfort with ranges of 5–45% and 55–100%, respectively, and lowered overall building energy consumption by 1–19% yearly, depending on the building's geographic orientation. [ABSTRACT FROM AUTHOR]

Human performance and health are among the most relevant topics in modern society, especially at young ages, when academic performance is indispensable. Thus, as humans spend most of their life inside a building, thermal comfort and indoor air quality are essential aspects of a room. The aim of the current study is to numerically evaluate the main thermal comfort parameters such as PMV and PPD as well as indoor air quality, i.e., CO2 concentration, in library group study rooms at the University of Gävle in Sweden. Rotroninc Measurement Solutions CL11 sensors were utilized for temperature measurements. Simulation models were created and validated based on building data as well as temperature measurements. Several simulations were conducted throughout the year, covering different periods. The results show that even though the ventilation system, with only temperature control, works as intended for maintaining thermal comfort, the CO2 concentration rises above 1000 ppm when more than one student occupies the rooms, which is not recommended by different thermal comfort ruling institutions. Consequently, a modification to the ventilation system control is recommended, changing it from temperature control to CO2 and temperature control.

This paper introduces a new measure for individual thermal comfort, inspired by the current standards for population thermal comfort, and a statistical model allowing us to imitate individuals’ thermal comfort preferences. Our approach is based on the observation that an individual has a temperature range around his or her desired temperature point in which he or she is comfortable with the surrounding thermal environment. The crucial parameters of our statistical model, which represents the thermal characteristic of individuals of building occupants, have been assumed to be normally distributed random variables so that the thermal comfort preferences of different individuals can be generated for the further simulation purposes. When aggregated to a population’s general thermal comfort parameters, the variables of these distributions have been adjusted in such a way as to bring very close consistency with the current standards, which define the criteria for acceptable thermal conditions of human occupancy in a built environment.

In automobiles, the demand for HVAC has been rising for decades and the key variables that affect the thermal comfort in a car were identified as air velocity, temperature, radiant temperature, and relative humidity. Thermal comfort estimation in a vehicle depends on the transient behavior of the cabin space and boundaries. The predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) are the available methods to describe and optimize thermal comfort in cabin space. In this paper, the cabin thermal comfort of a minivan was analyzed for reduction of energy consumption with the help of experimental and numerical simulation. Using CFD simulation and validation with experimental data, the flow dynamics inside a vehicle cabin is evaluated based on air velocity, temperature, and comfort indices. With some error for the extreme planes, a strong agreement was reached between the experimental values and the CFD model. With the reduction in the air velocity from 2.3 m/s to 1.3 m/s, the average power required to run the blower can be reduced by 43%, providing an advantage of reducing the capacity of the compressor. The higher PPD values were observed on the walls of the cabin and at the outlet of the AC vents. [ABSTRACT FROM AUTHOR]

In the present research, an investigation of the UFAD system for thermal comfort has been conducted in a high-rise building located in the tropics. The indoor air conditions including temperature, relative humidity, air velocity, and mean radiant temperature have been obtained by conducting the fieldwork while the clothing insulation value and the metabolic rate of the occupants have been obtained by observing the occupants, where these data were used to obtain the predicted mean vote (PMV) and the predicted percentage dissatisfied (PPD) of the examined areas. In addition, the effects of the airflow pattern in the indoor thermal comfort have been investigated, where two different types of diffusers have been compared in order to find out which diffuser can provide a better thermal comfort to the occupants. The FloEFD simulation software is used to simulate the airflow pattern of these diffusers and to analyze the indoor air conditions of the UFAD system and also to examine the local mean age value. Based on the results obtained, the average PMV is approximately − 1.5 for each examined area, where a proper design of heating, ventilation, and air-conditioning system in a hot and humid country, the PMV result should be approximately equal to − 1. As for the PPD, the range of the PPD obtained falls in between 27.4 and 67.5%, in which it indicates that about more than half of the occupants have dissatisfied with the indoor conditions in the examined building. [ABSTRACT FROM AUTHOR]

Thermal comfort is one of ergonomics factors that can create a significant impact to workers performance. For a better thermal comfort, several environment factors (air temperature, wind speed and relative humidity) should be considered in this research. The object of the study is a building for converting process of plastics manufacturing industry located in Malang, Indonesia. The maximum air temperature inside the building can reach as high as 36°C. The result of this study shows that heat stress is dominantly caused by heat source from machine and wall building. The computational fluid dynamics (CFD) simulation is used to show the air characteristic through inside the building. By using the CFD simulation, some scenarios of solution are successfully presented. Employees thermal comfort was investigated based on predicted mean vote model (PMV) and predicted percentage of dissatisfied model (PPD). Existing condition gives PMV in range from 1.83 to 2.82 and PPD in range from 68.9 to 98%. Meanwhile, modification of ventilation and replacing ceiling material from clear glass into reflective clear glass gave significant impact to reduce PMV into range from 1.63 to 2.18 and PPD into range from 58.2 to 84.2%. In sort, new design converting building process has more comfortable for workers.

Nowadays, the thermal comfort in the means of transport is an important field of research, which have a positive impact on the health of the passengers and the driver. The latest research, results and methods, to determining the comfort in means of transport are presented in the first part of the paper. The thermal comfort study is carried out on an existing bus geometry. The bus geometry is modelled in SolidWorks using blueprints available on the web. The simulation is done for three cases: the first case where the ventilation system is open at maximum capacity, the second case where the ventilation system works at maximum capacity whit the air deflectors mounted for a better distribution of the air and the last case when the bus velocity is 14m/s whit two rear windows opened. The results of the first simulations are analysed and a location of deflectors is proposed for an optimal distribution of air inside the bus. In the last part of the paper we compare the obtained results, highlighting the conclusions of this study.

The present paper reports on an experimental study performed in a seminar room of the University of Luxembourg in a building of the 1970ies without a major renovation. This lecture room is typical for this building period and has a capacity of 60 seats. It is equipped with a mechanical ventilation system that is normally in operation on workdays for 11 hours a day in semester periods (8:00–19:00h), while windows can be opened manually. A blower‐door test revealed that the room is not airtight. During a year, the ventilation system was shut "on" and "off" in periods of some weeks and the consumed final‐energy was measured, as well as the indoor climate assessed by physical and psychological measurements. For instance, the measured CO2 concentrations are marginally better with the ventilation system „on", which was not perceived in any way by the occupants during the investigations. It was not possible to properly identify the impact of ventilation on the consumed heat‐energy, as the room could not be thermally separated from the rest of the building. But with the system "on", there was a clear increase in consumed primary energy due to the electric consumption of the fans. No relationship between the perceived percentage of dissatisfied and perceived climate could be observed. It is concluded that the typical normal operation modus is questionable for seminar rooms in older buildings with variable occupancy and that a simple shut down or semi‐automatic user‐controlled modus by low‐cost retrofit seems advantageous. [ABSTRACT FROM AUTHOR]

The indoor thermal environment of buildings influences people's health, well-being and productivity, as well as energy consumption. The importance of thermal comfort in buildings has been recognized for decades. However, this aspect is still incipient in the Colombian construction industry, especially in housing projects. In this research, the thermal performance of three common housing types in the city of Medellin was analyzed. To do this, the operative temperature, the predicted mean vote (PMV) and the predicted percentage of dissatisfied (PPD) were calculated in accordance with ISO 7730:2005. The results showed that the thermal inertia of two of the three types of housing examined was insufficient to offer adequate thermal conditions, despite the temperate climate of the Aburra Valley. These results warn about the vulnerability of urban population in Colombia to extreme temperature fluctuations. [ABSTRACT FROM AUTHOR]

Nowadays, the thermal comfort in the means of transport is an important field of research, which have a positive impact on the health of the passengers and the driver. The latest research, results and methods, to determining the comfort in means of transport are presented in the first part of the paper. The thermal comfort study is carried out on an existing bus geometry. The bus geometry is modelled in SolidWorks using blueprints available on the web. The simulation is done for three cases: the first case where the ventilation system is open at maximum capacity, the second case where the ventilation system works at maximum capacity whit the air deflectors mounted for a better distribution of the air and the last case when the bus velocity is 14m/s whit two rear windows opened. The results of the first simulations are analysed and a location of deflectors is proposed for an optimal distribution of air inside the bus. In the last part of the paper we compare the obtained results, highlighting the conclusions of this study. [ABSTRACT FROM AUTHOR]

Abstract There is increasing evidence of adverse health impact of solid biomass fuel, and its use may hinder thermal comfort, which may lead to lower quality of life. Hence, current study aims to assess the thermal comfort at a rural location of Punjab, India. The indoor air temperature and relative humidity in rural households during winter varied from 11.9–25.2 °C and 63.4–90.5% respectively, during pre-summer it ranged between 21.3 and 27.4 °C and 48.4–78.4% while during summer it ranged between 28.4 and 37.8 °C and 13.7–63.8% respectively. The PMV of the households ranged between −0.85 to 0.69 (winter), −0.32 to 0.4 (pre-summer) and 0.53 to 1.25 (summer) for American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 55-2017 and −0.56 to 1.11 (winter), 0.04 to 0.99 (pre-summer) and 1.21–2.36 (summer) for European Committee for Standardization (CEN) European standard EN15251 while the Predicted Percentage of Dissatisfied ranged between 5 and 20% (winter), 5–8% (pre-summer) and 11–38% (summer) for ASHRAE 55-2017 and 5–31% (winter), 5–26% (pre-summer) and 36–90% (summer) for EN15251 guidelines. On the other hand, Adaptive thermal comfort (ATC) during winter and pre-summer was comfortable for 80 and 90% acceptable limits (ASHRAE-2017) and ranged between too cool to comfortable for EN15251 (Class I, II and III) while during summer thermal comfort for occupants was comfortable for ASHRAE 2017 and EN15251 (Class I, II, III) but did not comply with EN guidelines in some households using either clean fuel or chullah. Thermal comfort sensation was observed to be slightly cool to neutral during winter, neutral during pre-summer and slightly warm during summer according to Predicted Mean Vote method. The results were also compared using a thermal comfort and household survey and found to be similar with the model results. Climate change is leading to changes in temperature which may have an impact on the built environment. Hence, the current study suggests formulating policies on the uses of household fuel and design of kitchen with proper ventilation to increase thermal comfort which in turn will also reduce air pollutants. Graphical abstract Unlabelled Image Highlights • First study reporting the thermal comfort in rural households of India. • PMV of rural households ranged between -0.32 to 1.25 as per ASHRAE 55-2017 standards • Thermal comfort was observed slightly warm during summer months. • SBF not only causes household air pollution but also affects the thermal comfort. • Need to formulate policies to ensure adequate thermal comfort in households' microenvironments [ABSTRACT FROM AUTHOR]

Abstract In this study, we proposed a PMV-based method to evaluate the variations in thermal characteristics of the cabin of a submersible craft and the comfort levels of the crew during manned deep-sea missions. Based on the characteristics of tasks performed during a submersible deep-sea mission, we modified the criteria used by our model for clothing and activities, and then investigated other human factors found in the cabin as well. To test and verify our method, we used the averages of the environment data (depth, temperature, and humidity) from a Jiaolong mission that included six 7000 m deep-sea dives in the southern Mariana Trench. MATLAB was employed to calculate the PMV index and PPD, and to draw the PMV/PPD dynamic curves. The results showed that the PMV value changed constantly between [-2, +3]. The cabin thermal environment was dynamic and in continuous change, including a short period of a warm state and a long, continuous cold state. Because the submersible cabin lacked an air conditioning system, this paper analyzed the two-state thermal comfort based on regulating the air velocity of the ventilation system. Our detailed findings can be used by the submersible design institutes to evaluate the thermal comfort of oceanauts on manned submersibles, and to coordinate the energy distribution of air conditioning systems for cabins in the future. [ABSTRACT FROM AUTHOR]

Modern buildings with new heating, ventilation and air conditioning (HVAC) systems offer possibility to fit parameters of the indoor environment to the occupants’ requirements. The present paper describes the results of measurements performed in an office room in the first Polish passive commercial office building during four months of normal operation. They were used to calculate parameters describing thermal comfort: vertical air temperature profile, floor surface temperature, predicted mean vote (PMV) and predicted percent of dissatisfied (PPD). Obtained results confirmed good thermal conditions in the analysed room. The average temperature of the floor’s surface varied from 20.6 °C to 26.2 °C. The average vertical air temperature, calculated for working days, was from 22.5 °C to 23.1 °C. The temperature difference between the floor and 5 cm below the ceiling was from −0.9 °C to 6.3 °C. The PMV index varied from 0.52 to 1.50 indicating ‘slightly warm’ sensation, in spite of ‘neutral’ reported by employees. Also measured cooling and heating energy consumption was presented. The performed measurements confirmed the ability of thermally activated building system (TABS) to keep good thermal conditions.

Hospitals require the highest energy demands in non-residential buildings. They provide healthcare 24/7/365 and, at the same time, they ensure indoor air quality, thermal comfort and sterility. However, several studies reveal that high indoor temperatures and low relative humidity (RH) are often perceived in patient rooms during the heating season, suggesting an important energy saving potential. Against this background, radiant ceiling panel (RCP) systems result to be one of the most appropriate solutions as they allow to achieve significant energy savings while providing the highest level of thermal and acoustic comfort, as well as of infection control. In the present study the microclimatic survey of a patient room at Maggiore Hospital in Bologna, Italy, equipped with an air conditioning system integrated with RCP, has reported occupant thermal discomfort. Experimental data were used to calibrate a building model and dynamic building energy simulations were carried out to analyse indoor air temperature, relative humidity, predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) indexes under different inlet air temperatures, to identify the best design conditions for energy efficiency and thermal comfort improvement. It was found that the highest advantages can be obtained when neutral air is supplied.

Simulation tools are widely used to model buildings in order to predict their indoor air quality and energy consumption. The prediction capability of the model is an influential factor in determining the ability of the building to be energy efficient and thermally comfortable. Thus, the validation of the developed models is crucial. In this context, this paper presents a numerical model developed using an object-oriented modelling tool based on the Modelica approach and a case study validation of this model. Then the thermal behaviour of the building and the occupants’ thermal comfort in the considered case study are investigated. The objective is to validate the developed model firstly by comparing predicted results with measured data regarding room temperature and relative humidity, and secondly by comparing the calculated thermal comfort indices (PMV and PPD) based on predicted results and measured data. The results show good agreement between simulations and experiments, with a maximum error in room temperature and relative humidity of 1.7 °C and 4.5%, respectively, and only 1% and 1.5% difference between averaged values of PMV and PPD, respectively.

Abstract Thermal comfort is a subcategory of environmental comfort measured in the light of climatic conditions. Having a good climate is regarded as an advantage for any tourist attraction. The present study aimed at assessing thermal comfort of tourist attractions in Kerman. This cross-sectional descriptive-analytical study used ISO 7730 to evaluate thermal comfort in Kerman through both subjective and objective procedures. Data were collected on three different days of the six months of summer and winter. Three time intervals (8–9 AM, 11–12 PM, and 6–7 PM.) were set for data collection on each day. The results indicated that subjective and objective PMV had the highest correlation with dry temperature (r = 0.88 and r = 0.94, respectively). There was also a significant correlation between objective and subjective PPD (r = 0.91) and objective and subjective PMV (r = 0.97). According to the obtained results, subjective PMV is greater than objective PMV. In other words, subjective dissatisfaction is greater than objective dissatisfaction. Furthermore, according to the obtained values for subjective and objective PMV, thermal comfort is at the maximum level at 6–7 PM (during summer) and 11–12 AM (during winter). Policy makers should plan to attract a larger number of tourists in these times. Highlights • According to the obtained results, subjective PMV is greater than objective PMV. • Subjective dissatisfaction is greater than objective dissatisfaction. • According to the obtained values for subjective and objective PMV, thermal comfort is at the maximum level at 6–7 PM (during summer) and 11–12 AM (during winter). [ABSTRACT FROM AUTHOR]

It is a prime aim to ensure a suitable comfort level in case of office buildings. The productivity of office employees is directly influenced by the comfort. Thermal discomfort and poor indoor air quality deteriorate the intensity and quality of human work. We investigated the comfort in office buildings with on-site measurements during the summer season. The office buildings were operating with different HVAC (Heating, Ventilating and Air-Conditioning) systems: ducted fan-coil with suspended ceiling, installation, non-ducted fan-coil with floor-mounted installation, active chilled beam with fresh air supply. We evaluated the thermal comfort under PMV (Predicted Mean Vote), PPD (Predicted Percentage of Dissatisfied), the local discomfort based on DR (Draught Rate) and the IAQ (Indoor Air Quality) based on carbon dioxide concentration. The comfort measurements were evaluated. The measurements were evaluated with scientific research methods, comfort categories based on the requirements of CR 1752. The results of this comparison were presented in this article. [ABSTRACT FROM AUTHOR]

In this study, the relation between the thermal environment and the thermal comfort of occupants in a main line vehicle in the summer was investigated. At first, to understand the characteristics of the thermal environment in a main line vehicle, a field survey was conducted by measuring the temperature and humidity in regular passenger services from the morning to the night. The observation range of the temperature was from 23°C to 28°C, and that of the humidity was from 38%rh to 68%rh. Then, to obtain the fundamental data about the occupants’ thermal comfort, a subjective experiment in which 44 subjects in total participated was carried out. The subjects rode a main line vehicle stationed at a rolling stock center, and they experienced the temperature changing approximately in the range observed in the field survey and answered the questionnaires about their thermal comfort. Furthermore, the relationships between the thermal indices called PMV/PPD and the subjective evaluation values were analyzed. As a result, it was indicated that the error of the PPD in predicting the percentage of dissatisfied subjects became large in the range PMV>0, where the effect of the sweat sensation became significant. However, the PPD agreed well with the actual percentage of people who reported to have the feeling of ‘slightly cold’, ‘cold’ or ‘slightly hot’, ‘hot’. Our results suggest that the PPD can be used as an index of the variability of thermal sensation, but not as an index of thermal comfort in a main line vehicle in the summer; in order to use the PPD as an index of thermal comfort all the year around, it should be corrected taking into account the seasonal characteristics of the relation between the PMV and the actual percentage of dissatisfied occupants.

This paper pays tribute to Povl Ole Fanger, the late professor at the Technical University of Denmark. His scientific studies, focused on the main parameters affecting indoor environmental quality, have inspired (and still inspire) professional design engineers and academic researchers on human thermal comfort and indoor air quality over the last five decades. In addition, he strongly contributed to the creation of a “European School” that addressed engineering issues and was well integrated with the American School, which was characterised (at that time) by a physiological approach. Ten years after his death, this paper is a memorial of his research in the field of thermal comfort and some aspects of indoor air quality. Only the original papers of this Danish scientist will be discussed. The analysis of each single topic of his research and of its impact on past and present research would require more space than would be available in a review article. The authors are confident that the research described in this paper will serve as a beacon for researchers working on thermal comfort now and in the future. [ABSTRACT FROM AUTHOR]

The main aim of this study is a comprehensive analysis of long-term monitoring data of thermal comfort and discomfort parameters in small identical test buildings equipped with different heating/cooling systems. Calculations of PPD index expressed the human perception of thermal comfort and such discomfort factors like draught rate and vertical air temperature difference are provided for the room in winter season running three different heating systems - electric heater, air-air heat pump and air-water heat pump, as well as for the summer cooling with split type air conditioning systems. It is shown that the type of heating/cooling system and its working regime has a significant impact on thermal comfort conditions in the room. Recommendations for the optimal operating regimes and choice of the heating system from the thermal comfort point of view are provided. [ABSTRACT FROM AUTHOR]

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Energy conservation in buildings is a serious attention in Indonesia, including as one of the focus in the Roadmap Research, Development, and Application of Science and Technology Field of New and Renewable Energy Sources from the Ministry of Research and Technology. This study aims to determine the thermal calculator PMV” provided by Luma Sense Technologies to get the value of PMV-PPD and thermal comfort employee feels comfortable with the PMV value of 0.7 (slightly warm) and PPD value of 16.89 (mean 16.89% of people feel uncomfortable in the room), but when the air conditioner off at 12.00 am, the PMV value rose to 2.76 (Hot) and PPD 96.57 (mean 96.57% of people feel uncomfortable). As for the condition of the hall with AC On the value of PMV = 1.8 (warm), PPD value of 67.89 (mean 67.89% of people feel uncomfortable), and so the AC off at 12.00 pm, the PMV value rose to 3.1 (Hot) with PPD 99, 5 (mean everyone does not feel of State Islamic University of Suska Riau at Islamic center relies heavily on the use of air conditioning, so the AC Off the thermal comfort is reduced drastically, especially in the middle of the day and hot weather during the term of the study. Based on the analysis and discussion of design concepts found most appropriate to the condition of the building with the addition of the IC is the insulation of the building, with one of the alternative types of polyurethane foam insulation is spray applied a simple and practical and appropriate for buildings that have been standing.

Although the indoor thermal comfort concept has received increasing research attention, the vast majority of published work has been focused on the building environment, such as offices, residential and non-residential buildings. The present study aims to investigate the thermal comfort conditions in the unique and complex underground railway environment. Field measurements of air temperature, air humidity, air velocity, globe temperature and the number of passengers were conducted in the modern underground railway of Athens, Greece. Environmental monitoring was performed in the interior of two types of trains (air-conditioned and forced air ventilation cabins) and on selected platforms during the summer period. The thermal comfort was estimated using the PMV (predicted mean vote) and the PPD (predicted percentage dissatisfied) scales. The results reveal that the recommended thermal comfort requirements, although at relatively low percentages are met only in air-conditioned cabins. It is found that only 33% of the PPD values in air-conditioned cabins can be classified in the less restrictive comfort class C, as proposed by ISO-7730. The thermal environment is “slightly warm” in air-conditioned cabins and “warm” in forced air ventilation cabins. In addition, differences of the thermal comfort conditions on the platforms are shown to be associated with the depth and the design characteristics of the stations. The average PMV at the station with small depth is 0.9 scale points higher than that of the station with great depth. The number of passengers who are waiting at the platforms during daytime reveals a U-shaped pattern for a deep level station and an inverted course of PMV for a small depth station. Further, preliminary observations are made on the distribution of air velocity on the platforms and on the impact of air velocity on the thermal comfort conditions. [ABSTRACT FROM AUTHOR]

The Indoor Zero-Equation Turbulence Model in software Airpak was adopted to simulate the personal thermal comfort in the condition of displacement ventilation at the left side. The parameters of the simulated environment were 25°C and 40%. The simulated results show that over the person, there was a clear phenomenon of thermal plume which entrains the around air resulting in the decrease of the temperature with the increasing of the height. As for the predicted mean vote (PMV) and the percent person's dissatisfied (PPD), their gradient were depended on the temperature distribution formed by thermal plume, and the average value was 0.249 for PMV and 7.25% for PPD. All these show that the effect of thermal plume can not be neglected in the design of HVAC system. [ABSTRACT FROM AUTHOR]

The aim of this study is detailed analysis of long-term monitoring data of thermal comfort conditions and energy efficiency in small test buildings equipped with different heating systems. Calculations of PPD index and local thermal discomfort factors are provided for the test buildings during three weeks of heating season. It is shown that the type of heating system has influence not only on heating energy need, but also on thermal comfort conditions in the room. [ABSTRACT FROM AUTHOR]

Thermal radiation within buildings is a significant component of thermal comfort. Typically the methods applied for calculating view factors between a person and its building surfaces requires great computational time. This research developed a view factor calculation method suitable for building energy simulations. The method calculates view factors by numerical integration of projected area factor. Over time the projected area factor of a person has been simplified by geometrical shapes. These shapes were compared with more complex equations on precision and calculation time. The same was done for the resulting view factors, where the results were compared with view factors found by ray tracing. While geometrical simplifications of the human body gave the fastest calculations, the complex equations gave the most accurate results. Non-rectangular surfaces and obstacles were treated by comparing intersection points with the edges of the surface, making the method applicable to rooms with complex geometry. The method for calculating view factors is robust and applicable to building energy simulation tools. Calculation time can be long depending on the complexity of geometry, grid-size and the choice of method for the projected area factor, but view factor calculations are done only once for a whole year simulation. [ABSTRACT FROM AUTHOR]

Summer time is especially difficult to provide optimal conditions of the microclimate in heavily used areas. Choosing optimal materials and construction solutions is essential and can guarantee maintaining comfortable conditions inside the building in all seasons, even when outside temperatures reach high levels. This article focuses primarily on the effect of the heat capacity of construction materials on the thermal comfort in a passive school building. Cellular concrete, silicate blocks and solid brick were analyzed. The simulation was performed from 15th May to 15th September. Results presented in this article show that in order to protect the building from overheating, heavy materials with a high heat capacity are the most effective. In case when highly conductive materials were used, it can be observed that lower inner temperatures appear during summer and predicted mean vote values are close to the thermal comfort zone. [ABSTRACT FROM AUTHOR]

There are many parameters belonging to environmental or subjective kind and influencing thermohygrometric well-being conditions in both living and working places : thermo-hygrometric indexes measurable in the environment directly (Tba, Tbu, φa, va) or analytical ones (Tmr, Top) both give only a superficial and partial assessment of the environmental conditions because they do not take into account subjective evaluation parameters. The heat exchange - in case of sources of radiation marked by a surface temperature such different from the mean value of the remaining surfaces (for example a large glass surface in winter and / or summer conditions) - enhances the feeling of radiative heat exchange with the body surfaces of the exposed subject. The IS07726 standard "Thermal Environments-Instruments and Methods for Measuring Physical Quantities" has been developed to give guidance on the correct methods to be adopted in the measurement of environmental parameters; this paper presents a study on the influence of radiative exchange on the thermo hygrometric comfort in living and working environments. Two cases will be examined: case "A" with the radiant wall only formed by single wall named "1" from the wall, and case "B" with two radiating walls named "1" and "2". [ABSTRACT FROM AUTHOR]

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Worship places represent a unique type of buildings due to their functionality, dense occupancy, intermittent use, roof geometry, large inner space, and consumed energy of cooling/heating systems. In addition, thermal comfort and indoor air quality are decisive keys that affect the psychological and physiological conditions of occupants as well as their activity level and working efficiency. Though, a scarce number of studies focused on investigating the indoor conditions of worship places. Thus, a mosque located in Bahrain was selected to examine the influence of the occupancy level and period on thermal comfort sensation and indoor air quality. The readings of air temperature, humidity, air velocity, and CO 2 concentration were recorded during real several occupancy levels and periods during the summer season. The measured findings of PMV and PPD metrics indicated that the social distancing between worshippers, during the SARS-CoV-2 pandemic, causes a feeling of coolness under the existing cooling system. Meanwhile, the 2-h occupancy period produced a 75% increment of CO 2 concentration, 55% during 1-h occupancy, and 20% during half an hour occupancy. Therefore, the air-conditioning systems of worship places should be reconsidered in terms of ventilation rates and partial operating to provide comfortable conditions that accommodate different occupancy levels and periods. [ABSTRACT FROM AUTHOR]

Copyright of Technical Transactions / Czasopismo Techniczne is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global current requirement is to increase thermal comfort in residential and non residential buildings. A field survey was accomplished in a naturally ventilated university classroom in Bucharest, Romania, in winter and spring. Comfort parameters were measured and comfort questionnaires were distributed to the students. Questions were related to thermal sensation of the occupants. This paper compares the experimental results with the occupant's response. It analyzes the variation of Predicted Mean Vote (PMV) and Predicted Percent of Dissatisfied (PPD) with temperature. It is made a comparison between PMV and thermal sensation vote. The results show PMV values different from Thermal Sensation Vote (TSV) values which means there is a poor approximation of indoor comfort. In conclusion the comfort parameters should be reviewed and should be proposed other evaluation methods. Possible explanations are discussed in relation with thermal regime of the buildings. [ABSTRACT FROM AUTHOR]

This study numerically analyses a well-validated comprehensive work on IEQ in a naturally ventilated, occupied 3-dimensional office building with installed furniture and internal heat-generating surfaces. This study analyzes the effect of the inlet diffuser orientation (IDO) on the indoor thermal comfort (ITC) of occupants and the energy demand of the building for heating indoor air. The Optimization of ITC has also been calculated for the acceptable indoor occupant comfort and energy consumption. The study is valuable to analyze the relationship between IDO of 0 ° , 15 ° , 30 ° , 45 ° , 60°and 75 ° , on ITC and the energy consumption of the indoor environment. Different methods have been chosen to study the ITC of the occupants such as air temperature, air movement in the occupied zone, vertical temperature gradient, and PMV and PPD index according to ISO7730. The results show that under a uniform indoor air distribution, the variation in IDO considerably affects the ITC and energy consumption. Optimized ITC can reduce indoor energy consumption by 35.14%. The IDO slightly affects the PMV and PPD index. Occupant's legs are more sensitive to the naturally ventilated indoor environment due to the adverse effect of buoyancy force which may create the problem of the cold draft. For optimization of the ITC, the air temperature in the occupied zone plays a key role. • Numerical investigation of indoor environment quality and energy consumption of a modeled occupied building. • Effect of Inlet Diffuser Orientation on occupant comfort and indoor environment quality. • Assessment of PMV, PPD, temperature gradient, air temperature and velocity for indoor comfort. • Optimization of indoor thermal comfort for optimum energy consumption and thermal comfort. [ABSTRACT FROM AUTHOR]

Highlights: [•] Energetic and exergetic comparison of the human body. [•] Usage of summer season data. [•] Calculation of entropy generation of the human body. [•] Thermal comfort. [•] Determining predicted mean vote rate and predicted percentage dissatisfied rate for the human comfort. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the performance of air conditioning system and the level of thermal comfort are determined in a state hospital located in Kermanshah city in the west of Iran in winter and summer using the Predicted Mean Vote (PMV) model which has been presented by . The Predicted Mean Vote (PMV) and the Predicted Percentage Dissatisfied (PPD) indices were computed using the data acquired from the experimental measurements performed in the building. The results showed that the values of PMV in some parts of the building, both for men and women, are not within the standard acceptable range defined by ISO. It was found that the most thermal problems in winter occur in morning work shift, and the worst thermal conditions in summer occur in noon work shift. The t-test results revealed that there is no noticeable difference between the thermal conditions of some rooms and those of the surroundings. [Copyright &y& Elsevier]