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Thèse doctorat : Génie Civil : Villeurbanne, INSA : 2007. / Titre provenant de l'écran-titre. Bibliogr. p. 315-321.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Supervisor: Jerold W. Jones. Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (M. Eng)--Carleton University, 1992. / Also available in electronic format on the Internet.

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xiv, 152 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 133-136).

Energy use in buildings accounts for more than a third of global energy demand, with humans seeking to create comfortable internal environments year-round. In the UK, air or water active thermal mass systems have demonstrated viability at delivering energy efficient comfort to office spaces. Whilst an attractive proposition, there are limitations to the cooling capacity and dynamic thermal response, giving rise to overheating in poorly designed buildings. The thesis work presented documents the investigation into active thermal mass enhancement to a prototype ventilated hollow core sample. Through engineering modelling (CFD, Excel VBA and IES) and laboratory (DSC, component and thermal chamber) testing two solutions were tested (an active-PCM module suitable for retrofit and embedded cool water pipes), with results conveying a 1 to 3°C temperature reduction and 0.1 to 0.2 kWh/m2/day AC savings during summer conditions. COP figures up to 10.6 were achieved through temperature set-point controlled water and air activated thermal mass. Economic analysis was conducted with positive results with the active-PCM module becoming viable for the UK’s non-domestic ‘Green Deal’ at a price point of approximately £300 per module. Following the laboratory led, and simulation supported work it was possible to conclude that active thermal mass enhancements can provide financially-viable energy-efficient, thermal-comfort for non-domestic UK properties. However the extent of the benefit depends heavily on the building thermal demands, available technology and optimised system control. Further work should be conducted to; develop additional modelling tools, underpinned by the laboratory data generated, and optimise the novel active-PCM technology, suitable for lucrative target markets.

In order to replace a conventional air-conditioner (AC) based on vapour compression technology that directly has high global warming potential and also currently consumes the most fossil fuel primary energy in building sector of tropical countries for generating thermal comfort on sleeping purpose, other alternative green space cooling technologies, as thermoelectric cooling (TEC), has to be improved to have same performance with AC. This research aims to develop and investigate a performance of Solar-powered Thermoelectric Radiant Cooling (STRC) system, as the combination of TEC and radiant cooling (RC) that is well known in its low energy consumption advantage. The studies were conducted through calculations, CFD simulations, system performance simulations and experiments. The results of optimum STRC system design was proved to provide better thermal and air quality performances, while the result in energy performance was depended on the TEC’s COP and vapour condensation prevention. After novel developing of TEC’s cooling channel with combined helical and an oblique fin to induce effective secondary flows that highly reduced the TEC’s hot side temperature in this research, the COP was able to increase up to 175%. Meanwhile, a novel bio-inspired combined superhydrophobic and hydrophobic coating on RC panel were able to competently repel most condensed water droplets, leaving just tiny droplets that was hard to be seen by naked eye. Finally, the COP of STRC system from house model experiment in 1:100 scales under hot and high humid climate was as high as 2.1 that helped STRC to consume electricity 34% less than AC system. Along with other benefits, as no working fluid, noise-free and low maintenance needs, the return of investment (ROI) was studied to be only 5-6 years when being operated with grid electricity and 17-18 years with PV panel generated electricity.

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vii, 59 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 48-49).

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

The work presented in this thesis investigates design, computer modelling and testing a sub-wet bulb temperature evaporative cooling system for space air conditioning in buildings. The context of this evaporative cooling technology design is specifically targeted at locations with a hot and dry climate such as that prevailing in most regions of Middle East countries. The focus of this technology is to address the ever-escalating energy consumption in buildings for space cooling using mechanical vapour compression air conditioning systems. In this work, two evaporative cooling configurations both based on sub-wet bulb temperature principle have been studied. Furthermore, in these designs, it was sought to adopt porous ceramic materials as wet media for the evaporative cooler and as building element and use of heat pipes as heat transfer devices. In the first test rig, the prototype system uses porous ceramic materials as part of a functioning building wall element. Experimental and modelling results were obtained for ambient inlet air dry bulb temperature of 30 and 35oC, relative humidity ranging from 35% to 55% and intake air velocity less than 2 (m/s). It was found that the design achieved sub-wet bulb air temperature conditions and a maximum cooling capacity approaching 242 W/m2 of exposed ceramic material wet surface area. The wet bulb effectiveness of the system was higher than unity. The second design exploits the high thermal conductivity of heat pipes to be integrated as an effective heat transfer device with wet porous ceramic flat panels for evaporative cooling. The thermal performance of the prototype was presented and the computer model was validated using laboratory tests at temperatures of 30 and 35oC and relative humidity ranging from 35% to 55%. It was found that at airflow rates of 0.0031kg/s, inlet dry-bulb temperature of 35oC and relative humidity of 35%, the supply air could be cooled to below the inlet air wet bulb temperature and achieve a maximum cooling capacity of about 206 W/m2 of wet ceramic surface area. It was shown that the computer model and experimental tests are largely in good agreement. Finally, a brief case study on direct evaporative cooling thermal performance and environmental impact was conducted as part of a field trip study conducted on an existing large scale installation in Mina Valley, Saudi Arabia. It was found that the evaporative cooling systems used for space cooling in pilgrims’ accommodations and in train stations could reduce energy consumption by as much as 75% and cut carbon dioxide emission by 78% compared to traditional vapour compression systems. This demonstrates strongly that in a region with a hot and dry climate such as Mina Valley, evaporative cooling systems can be an environmentally friendly and energy-efficient cooling system compared to conventional vapour compression systems.