Air Conditioning Research Papers - Academia.edu (original) (raw)

This paper proposes a new, simple, yet accurate mechanical cooling tower model for the purpose of energy conservation and management. On the basis of Merkel’s theory and effectiveness-NTU method, the model is developed by energy balance... more

This paper proposes a new, simple, yet accurate mechanical cooling tower model for the purpose of energy conservation and management. On the basis of Merkel’s theory and effectiveness-NTU method, the model is developed by energy balance and heat, mass transfer analysis. Commissioning information is then used to identified, only three model parameters by Levenberg–Marquardt method. Compared with the existing models,

The field of mechanical engineering has a theme word called ―CHANGE‖ as its backbone. The new technological advancements and the needs of people have made us think about this project. Our project is maiden venture into the field of air... more

The field of mechanical engineering has a theme word called ―CHANGE‖ as its backbone. The new
technological advancements and the needs of people have made us think about this project. Our project is maiden
venture into the field of air temperature controlling and also deals with human comfort. Human comfort conditions
deal with the conditions of environment around you, viz. HOT & COLD. The control of temperature of air
around us is done by controlling the output water from the water cooler. Our project is a novel idea to control air
temperature around us by the incorporation of cooling system in a single unit. This unit would be an economic
utility at all places to provide comfort conditions to the people. ―Faster, mightier & smaller‖ is still the keyword for
every invention and development. In day-to-day world we concentrate on the compactness and efficiency of every
product. Keeping this in our thought I have designed and fabricate an economical and reliable unit known as ―Water
Cum Room Cooler‖(Three in one air conditioner). ―Human comfort is that condition of mind, which expresses itself
with the thermal environment‖. In our project three rival properties of cool water, hot water & cool air are obtained

The aim of this paper is to assess the expectations of hotel guests in relation to the services offered by the hotel. For the purpose of this research, data on 6,768 hotels located in 47 capital cities in Europe were collected from the... more

The aim of this paper is to assess the expectations of hotel guests in relation to the services offered by the hotel. For the purpose of this research, data on 6,768 hotels located in 47 capital cities in Europe were collected from the website www.booking.com. We have used all information available on the website regarding the hotels chosen on the basis of previously specified criteria, including ratings given by the registered users. The methods of partial correlation and hierarchical regression analysis were then conducted. Research results indicate that the number of stars is the most important factor that influences overall customer satisfaction in the hotel industry. We find that room price, the presence of air-conditioning in rooms, lobby bar, and free Wi-Fi are variables that positively correlate with customer satisfaction, whereas the number of rooms in hotel and distance from the city center are negatively correlated with customer satisfaction.

Although air leakage from ducts has previously been treated as insignificant and leakage testing as not cost effective, this paper demonstrates that even minor leakage can have a significant effect on plant energy consumption and... more

Although air leakage from ducts has previously been treated as insignificant and leakage testing as not cost effective, this paper demonstrates that even minor leakage can have a significant effect on plant energy consumption and greenhouse gas emissions. Recognising this, the recently published AS 4254.2:2012 reverses past practice and now mandates leakage testing of systems over 3000 L/s. Not only will reducing leakage reduce energy use and greenhouse gas emissions producing a better outcome for the building owner and community, but attention to issues raised in this paper will benefit the contractor by reducing or eliminating the need for costly rectification of leaks revealed by leakage testing. The paper examines the implications of the Standard's testing requirements and suggests extension of its scope.

Lecture note on Greenhouse Engineering

The energy demand for air-conditioning has increased continuously throughout the last decades especially in developed countries. This increase is responsible for a large rise of the electricity demand and a sharp increase in peak demand... more

The energy demand for air-conditioning has increased continuously throughout the last decades especially in developed countries. This increase is responsible for a large rise of the electricity demand and a sharp increase in peak demand due to the use of electrically driven vapour compression machines. The substitution by thermally driven cooling systems using renewable energy or waste heat is a

Considering school students spend up to one third of their day inside classrooms, it’s surprising how few detailed empirical studies have been conducted into how the thermal environment of classrooms affects students’ comfort and... more

Considering school students spend up to one third of their day inside classrooms, it’s surprising how few detailed empirical studies have been conducted into how the thermal environment of classrooms affects students’ comfort and performance. Whereas PMV tends to exaggerate warm discomfort for adults, the literature suggests it underestimate children’s actual thermal sensation, but there is no coherent explanation for this in terms of metabolic or other physiological differences to date. The aim of this study was to conduct a thermal comfort survey in actual classrooms with a view to empirically defining preferred temperatures, neutral temperatures, and acceptable temperature ranges for Australian school children, and to compare them with findings from adult populations. The study informs a thermal comfort (air conditioning) policy being developed for Australian schools. The survey was conducted in a mixture of Air-Conditioned (AC), Evaporative-Cooled (EC), and Naturally-Ventilated (NV) classrooms in 10 schools during the Austral summer of 2013. Both Primary (grade) school and high schools were included in the sample. The survey was conducted twice a day (morning and afternoon), and the survey period varied between schools, from one week up to three weeks. After quality assurance processing a total of 3,129 questionnaires were retained from the sample of students and 138 samples were from the teachers. An indoor operative temperature of about 22.5°C was found to be the students’ neutral and preferred temperature, which is generally cooler than expected of adults under the same thermal environmental conditions, confirming earlier research findings in the thermal comfort literature. Working on the industry-accepted assumption that an acceptable range of indoor operative temperatures corresponds to mean thermal sensations of -0.5 through +0.5 (ASHRAE 2013; ISO 2005), the present analysis indicates an acceptable summertime range for primary and high school students from about 18.5 through to about 26.5oC operative temperature. The paper concludes with hypotheses to explain differences between thermal comfort of children and adults.

Air conditioning system in a operating room has important role in providing a comfortable and healthy environment for the medical expert to work and to enhance their medical services. The cooling capacity is obtained from calculating the... more

Air conditioning system in a operating room has important role in providing a comfortable and healthy environment for the medical expert to work and to enhance their medical services. The cooling capacity is obtained from calculating the cooling load. Cooling load calculation is the basis for designing an air conditioning system. There are various factors affecting the calculation of cooling capacity which are: weather, humidity, room volume, number of occupants, outside air conditions and room materials used in the room. The
application of the air conditioning system is through the selection of the air conditioning technology.
The calculation of the air system is done at RS Sky Hospital Tarakan Hospital located in Jakarta with room temperature conditioned 22 °C and RH 50%. From the calculation of each factor produces a total cooling load value so that the air system for the installed operating room has a cooling capacity that is able to provide comfort.
The result of calculation of total cooling load was 66 [kW] with air requirement 3,370 CMH, then result from psychometric total cooling load got 60 [kW]. From the calculation results obtained cooling engine for air system that is AHU and Chiller by using brand Daikin with model AHU DM2-0410 in capacity 68 kW and Chiller with UAL-340 model at 100 [kW] or 28,4 [TR] capacity.
Keywords: Operation Room, Air Condition System, Cooling Charges, Psychometric

Recently accepted revisions to ASHRAE Standard 55—thermal environmental conditions for human occupancy, include a new adaptive comfort standard (ACS) that allows warmer indoor temperatures for naturally ventilated buildings during summer... more

Recently accepted revisions to ASHRAE Standard 55—thermal environmental conditions for human occupancy, include a new adaptive comfort standard (ACS) that allows warmer indoor temperatures for naturally ventilated buildings during summer and in warmer climate zones. The ACS is based on the analysis of 21,000 sets of raw data compiled from field studies in 160 buildings located on four continents in varied climatic zones. This paper summarizes this earlier adaptive comfort research, presents some of its findings for naturally ventilated buildings, and discusses the process of getting the ACS incorporated into Standard 55. We suggest ways the ACS could be used for the design, operation, or evaluation of buildings, and for research applications. We also use GIS mapping techniques to examine the energy-savings potential of the ACS on a regional scale across the US. Finally, we discuss related new directions for researchers and practitioners involved in the design of buildings and their environmental control systems.