Clarifying Optimum Setting Temperatures and Airflow Positions for Personal Air Conditioning System on Flight

In recent years, the demand for air travel has increased and many people have traveled by plane. Most passengers, however, feel stressed due to the limited cabin space. In order to make these passengers more comfortable, a personal air-conditioning system for the entire chair is needed. This is because the human body experiences discomfort from localized heating or cooling, and thus, it is necessary to provide appropriate airflow to each part of the body. In this paper, a personal air-conditioning system, which consists of six vertically installed air-conditioning vents, will be proposed. To clarify the setting temperature of each vent, the airflow around the passenger and the operative temperature of each part of the body is investigated using fluid simulation. In the simulation, the ideal temperature for each part of the body is defined and compared with the operative temperature to verify how close both temperatures are, resulting in determining the ideal setting temperature. The simulation result shows, that most parts of the body reach their ideal temperatures. In addition, the optimum setting temperature and position of each air-conditioning vent, which contribute to maintaining the thermal comfort of the human body on the plane, is clarified.

Analysis of ceiling type to produce energy efficient residential buildings: case study on housing design of puskim pu-bandung city

Many houses that exist on this earth. Therefore, it is necessary to have tactical and intelligent thinking in designing a home. Many things are rarely considered related to the effects of the design of building elements when related to the temperature or the energy produced. Existing background regarding efforts to reach a comfortable temperature can not only be solved in terms of mechanical systems, but the architectural approach can help and provide a comfortable effect for its inhabitants. This research was conducted to determine the level of thermal comfort or temperature in the room of a residential design that would be related to the size of energy consumption by applying several alternative designs or ceiling forms. This type of research is research using simulation methods through a computer model. The results showed the use of ceiling type Vaulted Ceiling was able to increase the Surface Inside Temperature value by 3 ° C when compared to the type of drop ceiling. The Mean Radiant Temperature value when using the ceiling vault type rises 0.6 ° C and on the acquisition of Operative, Temperature rises 0.3 ° C. The use of insulation material on the roof can significantly reduce Mean Radiant Temperature and Operative Temperature at 1.7 ° C at Mean Radiant Temperature and 0.8 ° C at Operative Temperature. Seeing the results of the simulation in this study, the recommended ceiling type is to use the drop ceiling type because it is quite capable of keeping the temperature in the room not too high so that thermal comfort can be achieved. However, if you want to apply a ceiling design with a model or type of drop ceiling, it is better to use additional insulation material so that the heat transmission temperature is not too high in the room.

INFLUENCE OF THE THERMAL AND LIGHTING PERFORMANCE IN CLASSROOMS ON THE COGNITIVE PRODUCTIVITY OF STUDENTS IN COLOMBIA

ABSTRACT This paper examines the influence of the thermal and lighting performance in classrooms on the cognitive productivity of students attending public schools in the principal three cities of Colombia: Bogota, Medellin and Cali. The methodology used involves the application of cognitive performance tests and thermal and visual perception surveys, along with measurements of climatic parameters in 34 classrooms of 14 schools in 2017 and 2018. The results were analyzed using transversal correlational regressions. Among the conclusions, this study found that the operative temperature turned out to be the most conclusive variable explaining cognitive performance relationships.

CFD Study on Thermal Implication towards Human Body in Office Environment

Temperatures are rising gradually around the world due to the issue of global warming. This condition also affects those who have to work for long hours. A comfortable work environment helps employees to increase work productivity. Thermal comfort is the occupant’s satisfaction with the surrounding thermal conditions. Therefore, the objective of this study is to evaluate the thermal environmental conditions of air conditioning through Computational Fluid Dynamics simulations. The distributions of environmental parameters such as air velocity, air temperature, radiant temperature, inside an o?ce room with air-conditioning are presented. Based on these distributions, spatial pro?les of Predicted Mean Vote Index (PMV) are obtained to illustrate thermal conditions intuitively. This study was conducted under controlled environment inside special laboratory. To achieve this model office environment has been built in an environmental chamber. The distribution of PMV indicates that operative temperature at the 23 oC shows that the PMV is comfortable. The value of PMV in operative temperature at 23 oC is 0.79 near the skin of an occupant. The research outputs provide useful information for designers of the air-conditioning system to build a comfortable indoor environment in the office environment.

Thermal Comfort Performance of Naturally Ventilated Royal Malaysian Police (RMP) Lockup in Hot and Humid Climate of Malaysia

Thermal comfort performance of three vacant naturally ventilated Royal Malaysia Police (RMP) case study lockups (LK1 in Penang, LK2 in Melaka & LK3 in Kuala Lumpur) was measured during monsoon change period from Northeast Monsoon to Southeast Monsoon. According to NGO’s report and previous studies, the lockups condition is very poor and hot which contribute to discomfort among detainees. The objectives of the study are to investigate thermal comfort performance of the lockups based on four environmental parameters (Ta, Tr, Va, & RH) through physical measurement, to predict thermal comfort performance based on operative temperature (To) and neutral operative temperature (Tneutop), and to compare the results with thermal comfort criteria recommended by ASHRAE 55 standard and previous thermal comfort studies in hot and humid climate. The results show that To and Tneutop reading of LK1 is exceeding the maximum range recommended by ASHRAE 55 and previous studies by 2% to 8% (To) and 1% (Tneutop) which categorizing LK1 condition as hot. This is mostly due to high hot airflow brought through an ineffective window opening. The results will be used as reference for improvement towards some aspects such as window opening, building finishes materials, space volume and building orientation in future lockup design.

How Can We Adapt Thermal Comfort for Disabled Patients? A Case Study of French Healthcare Buildings in Summer

This paper investigates adaptive thermal comfort during summer in medical residences that are located in the French city of Troyes and managed by the Association of Parents of Disabled Children (APEI). Thermal comfort in these buildings is evaluated using subjective measurements and objective physical parameters. The thermal sensations of respondents were determined by questionnaires, while thermal comfort was estimated using the predicted mean vote (PMV) model. Indoor environmental parameters (relative humidity, mean radiant temperature, air temperature, and air velocity) were measured using a thermal environment sensor during the summer period in July and August 2018. A good correlation was found between operative temperature, mean radiant temperature, and PMV. The neutral temperature was determined by linear regression analysis of the operative temperature and Fanger’s PMV model. The obtained neutral temperature is 23.7 °C. Based on the datasets and questionnaires, the adaptive coefficient α representing patients’ capacity to adapt to heat was found to be 1.261. A strong correlation was also observed between the sequential thermal index n(t) and the adaptive temperature. Finally, a new empirical model of adaptive temperature was developed using the data collected from a longitudinal survey in four residential buildings of APEI in summer, and the obtained adaptive temperature is 25.0 °C with upper and lower limits of 24.7 °C and 25.4 °C.

Commercial Building Thermal Mass Precooling for Conditioning Reduciton Under the Operative Temperature Metric

Building thermal mass precooling is highly variable due to the uncertainty of the convective heat transfer coefficient, and current research neglects the radiative cooling effects of reduced interior surface temperatures. The research presented aims to address the shortcomings of current research by modelling night ventilation through concrete slab hollow cores, increasing confidence in the heat transfer coefficient estimate; and modelling the operative temperature experienced by an occupant in an open office with simplified geometry. The cooling load of a baseline non-ventilated slab was determined through a custom numerical model and the operative temperature of the baseline was assigned to the same model with hollow core slab ventilation to determine the ambient air setpoint temperature associated cooling load. The ventilated model was found to achieve 35% cooling energy savings compared to the baseline, with compromised occupant comfort in the early morning, and improved occupant comfort for the rest of the day.

Commercial Building Thermal Mass Precooling for Conditioning Reduciton Under the Operative Temperature Metric

Building thermal mass precooling is highly variable due to the uncertainty of the convective heat transfer coefficient, and current research neglects the radiative cooling effects of reduced interior surface temperatures. The research presented aims to address the shortcomings of current research by modelling night ventilation through concrete slab hollow cores, increasing confidence in the heat transfer coefficient estimate; and modelling the operative temperature experienced by an occupant in an open office with simplified geometry. The cooling load of a baseline non-ventilated slab was determined through a custom numerical model and the operative temperature of the baseline was assigned to the same model with hollow core slab ventilation to determine the ambient air setpoint temperature associated cooling load. The ventilated model was found to achieve 35% cooling energy savings compared to the baseline, with compromised occupant comfort in the early morning, and improved occupant comfort for the rest of the day.

Analyzing and modeling thermal complaints in a commercial building in France

Buildings are interactive environments in which their operations and occupants are linked. Although buildings are operated according to the standards, occupant complaints may arise when there is a mismatch between indoor environmental conditions and actual user needs. Therefore, the accuracy of thermal comfort prediction models suggested by the standards and alternative prediction models need to be investigated. This study aims at assessing the performance of the predicted mean vote (PMV) model suggested by the ISO 7730 Standard to detect occupant thermal dissatisfaction. In addition, a multivariate logistic regression model was developed to predict thermal complaints with respect to “too warm” and “too cold.” This case study was conducted in a commercial building located in Paris, France, between January 2017 and May 2018. Indoor environmental conditions were monitored via sensors and an online tool was used to collect occupant thermal complaints. A total of 53 thermal complaints were analyzed. The results showed that all the operative temperature measurements in both the heating and cooling seasons were within the thresholds suggested by the standards. The PMV method suggested that only 4% of the occupants were dissatisfied with the indoor environment whereas the actual dissatisfaction ratio was 100% under these indoor environmental conditions. In addition, the multivariate logistic regression model showed that operative temperature and season have a significant effect on thermal complaints. Furthermore, the accuracy of the developed model was 90.6%.