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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

The Stakeholders Using Strategy of Diversification for Taiwan's Business Transformation: Case on Air Conditioning Industry

Hung, Li-Yun 06 September 2012 (has links)
As environmental protection issue become the most hot global issues recently, Air Conditioning Industry has to face not only its own management and marketing problems, but also the responsibilities to environmental pollution. Thus, how to deal with the external pressure, the international regimes, and internal pressure become more and more important toward Air Conditioning Industry. How could Air Conditioning Industry take balance between international regimes and its own growth and profit? In addition, it also briefly discusses how Air Conditioning Industry could use its own resource and the strategy of diversification to create different road, making a high pollution industry transform to a green industry. Thus, this study is divided into external and internal factors which make AC industry have to change by strategy of diversification, and cases studying of how Air Conditioner transform itself to fit in the external rapidly changing world. The transformation relies on the effort and cooperation of stakeholders of government, association, and enterprises. Consequently, how these stakeholders achieve the goals on development of Taiwan's heat pump market might be more and more important on Air Conditioning Industry's future.
342

Psychrometric Testing Facility Restoration and Cooling Capacity Testing

Cline, Vincent E. 2010 August 1900 (has links)
The Psychrometric Testing Facility at the Riverside Energy Efficiency Laboratory at Texas AandM University has not been operational for several years. The goal of this project was to restore the testing facility to a fully operational condition for the purpose of supporting research and cooling capacity testing, with the latter following the appropriate standards. Numerous changes were made to the coolant piping system, the data acquisition system, instrumentation, and temperature and humidity control to update and improve the facility. In addition, a computer program was developed and implemented that allows for flexible control of the facility’s conditions and collection of data while showing real time performance and refrigerant and psychrometric calculations. The current program flexibility, along with the proper combination of instrumentation, allows the Psychrometric Facility to operate with separate steady state environmental conditions in each room, according to, and meeting, the AHRI 210/240 standard. Cooling capacity testing done on a split system residential unit was compared to the published AHRI rating to benchmark the state of the facility. Tested cooling capacity was about 3 percent below the published cooling capacity; tested EER was about 7 percent below the published EER; and finally, the calculated SEER based on the default degradation coefficient was about 10 percent below the published SEER. The difference in the calculated performance parameters to the published are expected due to unknown testing conditions used to calculate the published rating.
343

Analysis and Experimental Investigation on Energy Consumption of a Science and Technology Museum

Fan, Jia-wei 31 May 2005 (has links)
In this study, buildings in southern Taiwan area were selected to perform full-scale energy auditing experiment so that the energy consumption of each building can be analyzed comparatively. The result of experimental investigation and computer simulation were compared analytically with good accuracy obtained. The result can further facilitate as the design guide and energy indexes to be adapted in the national building energy code in the future
344

A study of heat pump fin staged evaporators under frosting conditions

Yang, Jianxin 30 September 2004 (has links)
This dissertation provides a detailed description of the research work completed on fin staged heat exchangers. The effects of staging fin on the frosting performance of heat pump evaporators and the whole heat pump system have been studied experimentally and theoretically. Frost degrades the performance of fin-and-tube outdoor coils as well as the whole heat pump system. The objective of the experimental part of this study was to investigate the effects of the staging fin on the frost/defrost performance of heat pump outdoor coils under different operating conditions. To accomplish this objective, a series of frosting tests was conducted on an off-the-shelf heat pump system with five (three two-row and two three-row) evaporators over a range of outdoor temperatures and humidities and a range of airflow rates typical of those found in residential sized heat pumps. Performances of the heat pump unit with baseline or fin staged outdoor coils at either frosting or steady-state test conditions are compared and analyzed. Experimental data showed that for a given tworow heat pump outdoor coil operating at the standard ANSI/ASHRAE 35 °F (1.7 °C) frosting conditions, fin staging increased cycle time and COP. There was a small decrease in peak capacity at lower initial airflow rates. At a lower temperature of 28 °F (2.2 °C), cycle time continued to be enhanced with fin staging, and cyclic COP was within 5% of the base case when fin staging was used. In the second step of this work, an analytical model to simulate the performance of both the baseline and fin staged heat pump coils under frosting conditions was developed based on fundamental heat and mass transfer principles. The transient performance of the frosted evaporator was analyzed with the quasi-steady state approach. The section-by-section evaluation scheme was combined with the tubeby- tube approach to model the mass transfer process in the frost formation module. The two-dimensional fin surface was divided into a number of parallel non-overlapping sections. Each of the sections was the calculation unit for the mass transfer. Methods for calculating the airside heat transfer coefficient and friction factor were developed and applied to the simulation model of the fin staged coil. To verify the validity of the frosted evaporator model, the frosting performance of three two-row coils at the same test conditions was simulated and compared with experimental data. The frosted evaporator model appeared to provide satisfactory simulation of the fin-and-tube heat exchanger during the frost buildup process. Comparisons with the test data indicated that the model could capture the trends of the coil capacity, pressure drop, airflow and frost growth. The model also provided a variety of other simulation results including frost mass accumulation, air velocity inside coil, air and refrigerant outlet state, and so on. Overall, the numerical results were in reasonable agreement with the test data under different frosting operation conditions.
345

Investigation on a solar powered absorption air-conditioning system with partitioned hot water storage tank /

Li, Zhongfu. January 2001 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 205-216).
346

Predicting the capital cost of air conditioning installations in high rise commercial buildings /

Wills, D. J. January 1986 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1987.
347

The Monitoring and Evaluation of Geothermal Systems

Maynard, Whitney E. 22 October 2010 (has links)
With the heightened importance of green engineering in today’s society, harnessing the Earth’s internal energy has become ever more important. Specifically, the use of geothermal heat pumps as a means of heating and cooling homes and municipal buildings is on the rise. However, due to the high cost of installation and limited amount of research conducted, geothermal systems in the State of Florida have yet to meet their potential as an alternative heating and cooling source. With Florida’s relatively constant ground temperature of 72 °F, an above average temperature gradient for both heating and cooling of indoor areas is provided. To this end, this thesis investigates different geothermal systems and their ability to utilize ground energy storage. To conduct this research, four different geothermal systems were installed and monitored over a period of one year. Testing of the installed systems monitored not only overall efficiency, but also the soils reaction to heightened energy input. Conclusions and recommendations are made as general design parameters for vertical column geothermal well systems in the state of Florida.
348

Experimental and theoretical investigation of a novel thermal storage system for electric vehicle climate conditioning

Fleming, Evan 20 November 2013 (has links)
A prototype thermal storage system, using phase change materials, was developed for a novel electric vehicle climate conditioning application. The proposed system consists of a heat transfer fluid circulating between either an on-board hot or cold thermal storage unit, which we refer to as thermal battery, and a liquid-air heat exchanger that provides heat exchange with the incoming air to the vehicle cabin. The research presented herein focuses primarily on the development of the on-board system and hot battery. While the air conditioning system was developed strictly for laboratory use, it was designed to meet application realistic performance metrics, e.g., a heat dissipation rate of 2 kW. The prototype was tested with three phase change materials: paraffin wax, xylitol, and erythritol. Furthermore, a full system thermodynamic model was developed to predict thermal performance that features semi-analytic solution to the coupled forced convection and phase change conduction heat transfer. Modeling results are compared against a numerical benchmark as well as our own experimental data. / text
349

Optimization of building cooling system based on genetic algorithms and thermal energy storage

Wong, Kin-chuen, 黃健全 January 2011 (has links)
published_or_final_version / Mechanical Engineering / Master / Master of Philosophy
350

Dynamic response of a cooling and dehumidifying coil to variations in air flow rate

葉啓明, Ip, Kai-ming. January 1997 (has links)
published_or_final_version / Mechanical Engineering / Master / Master of Philosophy

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