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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.
191

The application of the 'fabric first' approach to improve thermal comfort and energy efficiency in affordable housing in southern Brazil

Camboim Salatino Tubelo, Renata January 2016 (has links)
In 2009 the Brazilian government committed to support the construction of nearly 24 million new dwellings by 2022 through its housing programme Minha Casa, Minha Vida (My House, My Life). The initiative aims to tackle the housing shortfall of 5.546 million residential units and the 10.948 million units that are considered inadequate dwellings with poor living conditions. The potential economic, social and environmental impact of such large initiative is vast and consequently it is essential that the new dwellings are planned, designed and built to meet high levels of energy efficiency and thermal comfort. The ‘Fabric First’ is widely recognised as a design approach with great potential to deliver energy efficient and comfortable housing in a variety of different climates. Its principles have already been successfully incorporated in many buildings across European countries and elsewhere. Despite its success, research to date shows that the application of this approach has not been explored yet in the Brazilian context. In this work, ways of improving the thermal comfort and performance of Brazilian mass housing in three cities in southern Brazil (Curitiba, São Paulo and Porto Alegre) through the Fabric First principles were explored. The research was developed through sensitivity analyses of key envelope parameters and case studies. The sensitivity analysis was carried out in order to identify the best performance and the most cost-effective building envelope combination, using a simplified affordable Brazilian housing typology model that had its properties varied. A case study based on a generic representative model and a real optimised case study of typical 1-floor 2-bedroom mass housing typology were evaluated through computational thermal simulations and monitored data. The results of the sensitivity analyses were then used to inform the case studies performance analyses, developed in parallel to a cost analysis. Key findings from this study revealed that typical Brazilian building envelopes underperformed by up to 65% compared to super-insulated envelopes in terms of thermal comfort. In the real case studied this could represent up to 75% less thermal comfort. However, the additional costs of a super-insulated envelope showed to be 56-66% higher than the typical Brazilian envelope, with a payback period nearing the lifespan of the houses. In addition, it has been shown that relatively small improvements in the current building envelope could impact the upfront costs by only 6-12% but result in comfort improvement of about 45% against typical levels. These small improvements appear to be more suited to the cultural and economic Brazilian context and therefore are recommended as the best way forward.
192

Simplified sizing and selection of HVAC systems

Ox, Ivan 03 July 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MEng (Mechanical Engineering))--University of Pretoria, 2007. / Mechanical and Aeronautical Engineering / unrestricted
193

Modelování prostředí v kabině malého dopravního letadla / Simulation of indoor environment in a small transport aircraft cabin

Knapčík, Lukáš January 2011 (has links)
The diploma thesis is focused on ventilation and simulation of heating in small transport aircraft EV-55 cabin. First part explains an impact of thermal environment on human health and describes restrictions and recommendations forced on inner aircraft environment. In the first part are also clarified conditions of comfortable environment and thermal comfort evaluation for passengers via PMV and PPD index. The second part contains results from simulation of aircraft cabin environment. Inlet ventilation airflow and cabin heating is simulated via simulation mean Theseus-FE 3.0. The simulation results are evaluated for thermal comfort degree and optimal cabin insulation with optimal temperature and volume flow rate of inlet air is specified.
194

Nocturnal cooling of a solar collector-storage unit

Janke, Edward Lee. January 1978 (has links)
Call number: LD2668 .T4 1978 J35 / Master of Science
195

Ventilation for controlling airborne infection in hospital environments

Qian, Hua, 錢華 January 2007 (has links)
published_or_final_version / abstract / Mechanical Engineering / Doctoral / Doctor of Philosophy
196

The role of multiple courtyards in the promotion of convective cooling

Ernest, Raha January 2011 (has links)
This study is set out to confirm the phenomenon commented on by Hassan Fathy (1986) that the temperature difference between courtyards has a role in the promotion of convective cooling through transitional spaces in a multiple-courtyards building in semi and regions. The transitional spaces situated between courtyards are identified with specific titles such as Takhtabüsh in the Egypt; and Tablinum in a Roman Domus. However, despite the historic significance of these spaces, most studies have mainly focused on the climatic performance of buildings with a single courtyard. Empirical and numerical study has not been conducted on the nature of this phenomenon. In order to confirm this conjecture, this thesis is set out to conduct fieldwork and theoretical investigation. This thesis is a single case study of the Casa de Pilatos in Seville, Spain. The case study is used to develop a methodology for analysis of multiple-courtyard phenomenon. Field measurement and mathematical models are used to determine the drivers for yard-to-yard airflows. The fieldwork uses data logging equipment to record dry bulb temperatures, relative humidity, and air velocity through the transitional spaces. The amount of cooling attributed to yard-to-yard flows and implication to cooling requirements in a contemporary environment are evaluated. Adaptive criteria of Nicol and Humphrey (2001)'and Brager and de Dear (2001) are used to predict the thermal comfort of subjects. The drivers are determined through analysis of buoyancy `stack' forces and local wind regime. The building mass introduces three hours delay with up to 2.5kW or 36W/m2 variation in heat balance in the transitional spaces by 15: 00h. The calculated volume flow rates through the transitional space are 5.3m3/s (equivalent to 5kW or 71 W/m2 in convective cooling) at 15: 00h. The DBT in the gardens are up to 11 k below the WBT. It is shown that multiple-courtyards phenomenon is a robust strategy accommodating a large variation in temperatures. The study confirms that temperature difference is the driver for convective flows through transitional spaces. This study presents an opportunity to investigate the applicability of this concept in the contemporary context. Findings of this study have direct application in the reduction of cooling energy in widely used courtyard concept in semi and regions.
197

Computerized heat loss evaluation of farrowing houses

George, Herschel C January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
198

Keeping warm in New England : a history of residential heating from colonial times

Brown, David Whipple January 1976 (has links)
Thesis. 1976. M.Arch.--Massachusetts Institute of Technology. Dept. of Architecture. / Microfiche copy available in Archives and Rotch. / Bibliography: leaves 171-174. / by David W. Brown. / M.Arch.
199

Validation and refinement of a dynamic digital model of a fan coil heating system

Anand, N. K January 2011 (has links)
Photocopy of typescript. / Digitized by Kansas Correctional Industries
200

Wake survey behind a rotating ventilator

Rashid, Dewan Md. Harunur, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2002 (has links)
With environmental concern growing in both affluent and developing countries, roof top ventilators, a form of natural ventilation requiring only wind energy to ensure quality air circulation and comfort is becoming a considered choice of many households and industries. Unfortunately, however, many of these ventilators have evolved through trial and error and the flow physics associated with these ventilators is barely understood. The present experimental project was, therefore, undertaken as part of UNSW- Industry collaboration program funded under an Australian Research Council Grant to explore whether the aerodynamics forces acting on these ventilators during their operation could be obtained. A commercial roof top ventilator supplied by industry was, therefore, tested in an open jet wind tunnel of the University of New South Wales and the results are presented in this thesis. A novel feature of this project is the examination of the suitability of ???the three dimensional wake traverse??? technique to the wake of rotating ventilator. This technique has so far been applied with limited success to the wake of lifting bodies of fixed wing configuration only. In the absence of adequate data in the literature on rotating ventilator, the aerodynamics force components obtained by this technique have been compared against force balance measurements. The results show that the wake traverse technique is capable of determining lift and total drag forces associated with the ventilator flow during its operation from the pressure and velocity information gathered downstream of a ventilator in its wake. Generally, from these data, the technique also allows isolation of the profile and induced components of the drag force. However, from the induced drag value, while it is possible to determine the lift force, it is however, found that a more accurate value of lift force can be evaluated using axial vorticity formulation. The availability of the above technique which does not require measurements on the test specimen itself, will aid in providing a cost efficient investigation of the aerodynamic forces and consequently the performance of a roof top ventilator.

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