Evaluation of Thermal Comfort in an Air Conditioning Room Using a CFD Model

2011 ◽  
Vol 354-355 ◽  
pp. 717-721
Author(s):  
Fu Qiang Guo ◽  
Rui Bin Mei ◽  
Lei Zhang ◽  
Jun Wei Fan ◽  
Min Xue Li ◽  
...  

In order to obtain the thermal comfort work environment, the distribution of temperature and airflow velocity in typical computer room of school building is discussed with different supply air angles and velocities of incidence by CFD model. The calculated temperature after cooling in the room has a good agreement with the measured value. Furthermore, the distribution of temperature and airflow is uniform and the environment is comfort for working with supply air angles and velocity of incidence 45° and 60° and supply air velocity of incidence 1m/s comparing with that of other parameters. Additionally, the change of temperature becomes slow down with the increment of time and the air-conditioning has less influence on the change of temperature after about 900s with supply air angle and velocity of incidence 45°and 1m/s, respectively. The research is of great significance both in theory and practice to design air conditioning systems and evaluate the thermal comfort conditions.

2018 ◽  
Vol 22 (6 Part A) ◽  
pp. 2597-2604
Author(s):  
Razika Kharchi ◽  
Khaled Imessad

A significant portion of energy consumed in buildings is due to energy usage by heating, ventilation, and air conditioning systems. Free cooling is a good option for energy savings in the systems. In recent years, scientists, engineers, and architects designed successful and innovative buildings which use passive cooling techniques, such as natural ventilation. The house studied in the present work, is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of the integrated building (CNERIB) in the framework of the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house under consideration has a surface area of 65 m2 and is located in the region of Algiers which characterized by a Mediterranean climate with relatively mild winters and a hot and humid summer. The aim of this work is to study the thermal comfort inside the house in summer without air conditioning systems, only ventilation is considered. The aim of this work is to study the effect of natural ventilation on both thermal and hygrometric comfort inside the house during the summer period. Numerical simulation is made using the TRNSYS software and the results obtained are in good agreement with measured values. The prototype home is designed in a way that natural ventilation allows thermal comfort which induced energy saving from air conditioning. The mean temperature measured in the interior of the house is 26?C. The relative humidity reaches about 70% in August. Thermal comfort is related to relative humidity that are the essential parameters of the feeling of comfort. Humidity is an important parameter in thermal comfort, it is why we can conclude that we have reached a relatively good hygrothermal comfort.


2014 ◽  
Vol 493 ◽  
pp. 74-79
Author(s):  
Y.A. Sabtalistia ◽  
S.N.N. Ekasiwi ◽  
B. Iskandriawan

Energy consumption for air conditioning systems (air conditioning system) increased along with the increasing need for fresh air and comfortable in the room especially apartments. FAC system (Floor Air Conditioning) is growing because it is more energy efficient than CAC (Ceiling Air Conditioning) system. However, the position of the AC supply is on the lower level at the FAC system causes draft discomfort becomes greater as air supply closer to the occupants so that thermal comfort can be reduced. Heat mixture of windows, exterior walls, kitchen, and occupants in the studio apartment affect thermal comfort in the room too.This study aims to determine the position of the AC supply which has the best thermal comfort of FAC system in the studio apartment. It can be done by analyzing ADPI (Air Diffusion Performance Index), the distribution of air temperature, wind speed, RH (Relative Humidity), and DR (Draft Risk) to change the position of the AC supply supported by CFD (Computational Fluid Dynamics) simulation.This result prove that AC position 2 (on wall near the kitchen) is more comfortable than AC position 1 (on the bathroom wall) because AC position 2 away from occupied areas, thereby reducing the occurrence of draught discomfort.


2021 ◽  
pp. 108432
Author(s):  
Peiping Zheng ◽  
Chunxiao Wang ◽  
Yanchen Liu ◽  
Borong Lin ◽  
Huijun Wu ◽  
...  

Author(s):  
Somaye A. Mohamadi ◽  
Abdulraheem J. Ahmed

<span>Despite their complexity and uncertainty, air conditioning systems should provide the optimal thermal conditions in a building. These controller systems should be adaptable to changes in environmental parameters. In most air conditioning systems, today, there are On/Off controllers or PID in more advanced types, which, due to different environmental conditions, are not optimal and cannot provide the optimal environmental conditions. Controlling thermal comfort of an air conditioning system requires estimation of thermal comfort index. In this study, fuzzy controller was used to provide thermal comfort in an air conditioning system, and neural network was used to estimate thermal comfort in the feedback path of the controller. Fuzzy controller has a good response given the non-linear features of air conditioning systems. In addition, the neural network makes it possible to use thermal comfort feedback in a real-time control.</span>


2017 ◽  
Author(s):  
Abhijeet Chothave ◽  
Yashwant Mohite ◽  
Vinay Poal ◽  
Phaneendra Pamarthi

2013 ◽  
Vol 7 (2) ◽  
pp. 192-206 ◽  
Author(s):  
Jacqueline Elhage Ramis ◽  
Emmanuel Antonio dos Santos

To evaluate airports' current thermal comfort temperature and humidity were registered in three main Brazilian international airports, other variables were local region climate characteristics and the constructive types of passenger terminal buildings. The Brazilian air transportation demand has considerably grown over the last decade, with some airports reaching their capacity. Thermal discomfort may be a key driver of passenger perceptions of airport service levels, specially under capacity overload situations. Therefore, to achieve airport thermal comfort within this new scenario, and with the imminent and future expansions of the airport system, certainly put extra work on the existing air conditioning systems, consequently increasing energy consumption and its associated costs. Collected temperature and humidity from each study case subsided the data for the psychrometric charts. The evidences showed temperatures below the international standards requirements for thermal comfort levels. These charts also indicated that adequate building types with natural air circulation, provides the best levels of thermal comfort. Results suggest the importance of considering the implementation of a combined system using artificial and natural air conditioning in the planning of future expansions.


Author(s):  
Ghezlane Halhoul Merabet ◽  
Mohamed Essaaidi ◽  
Driss Benhaddou

Thermal comfort is closely related to the evaluation of heating, ventilation, and air conditioning systems. It can be seen as the result of the perception of the occupants of a given environment, and it is the product of the interaction of a number of personal and environmental factors. Otherwise, comfort issues still do not play an important role in the daily operation of commercial buildings. However, in the workplace, local quality effects, in addition to the health, the productivity that has a significant impact on the performance of the activities. In this regard, researchers have conducted, for decades, investigations related to thermal comfort and indoor environments, which includes developing models and indices through experimentations to establish standards to evaluate comfort and factors and set-up parameters for heating, ventilation, and air conditioning systems. However, to our best knowledge, most of the research work reported in the literature deals only with parameters that are not dynamically tracked. This work aims to propose a prototype for comfort measuring through a wireless sensor network and then presenting a model for thermal comfort prediction. The developed model can be used to set up a heating, ventilation, and air conditioning system to meet the expected comfort level. In particular, the obtained results show that there is a strong correlation between users’ comfort and variables such as age, gender, and body mass index as a function of height and weight.


2020 ◽  
Vol 10 (4) ◽  
pp. 1513 ◽  
Author(s):  
Daniel Sánchez-García ◽  
David Bienvenido-Huertas ◽  
Jesús A. Pulido-Arcas ◽  
Carlos Rubio-Bellido

Reports of Intergovernmental Panel on Climate Change have set various greenhouse gas emissions scenarios, through which the evolution of the temperature of the planet can be estimated throughout the 21st century. The reduction of the emissions from the different activities carried out by mankind is crucial to mitigate greenhouse gas emissions. One of the most significant activities is users’ behaviour within buildings, particularly the use of Heating, Ventilation and Air-Conditioning systems. Modifying users’ behaviour patterns to guarantee acceptable thermal conditions inside buildings could lead to considerable energy saving percentages, and adaptive thermal comfort models could be an opportunity to achieve important savings. For this reason, this study analyzes the potential to apply adaptive thermal comfort models to use artificial air-conditioning systems by modifying setpoint temperatures. The analysis was conducted in five major European cities (Barcelona, Berlin, Bern, Rome, and Vienna) and in five climate change scenarios in the year 2050. The results showed that, in general, the energy saving achieved by adaptive strategies was larger in the cities with a greater cooling demand. Also, in both Representative Concentration Pathways (RCP) of the Fifth Assessment Report (AR5) considered, the energy saving were decreased in the cities of Barcelona and Rome, with values lower than those of the Fourth Assessment Report (AR4) scenarios considered, whereas in the cities of Berlin, Bern, and Vienna, the saving in the RCP scenarios is greater than those in the other scenarios.


2015 ◽  
Author(s):  
Rafael Prata Ritzinger ◽  
Nathane Ventura de Miranda ◽  
Álvaro M. Bigonha Tibiriçá ◽  
Alexandre Navarro da Silva ◽  
Henrique Márcio Pereira Rosa ◽  
...  

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