18 resultados para Collectors and collecting
Resumo:
A theoretical approach has been used to evaluate the performance of facade integrated solar collectors based on the physical collector parameters such as absorber plate absorptance, transmittance of the glazed cover plate and insulation thickness. A 1D steady state model, based on the Hottel Whillier Bliss equation, was employed to determine the effect of changing parameters to meet façade integration criteria.
Resumo:
A low cost flat plate solar collector was developed by using polymeric components as opposed to metal and glass components of traditional flat plate solar collectors. In order to improve the thermal and optical properties of the polymer absorber of the solar collector, Carbon Nanotubes (CNT) were added as a filler. The solar collector was designed as a multi-layer construction with an emphasis on low manufacturing costs. Through the mathematical heat transfer analysis, the thermal performance of the collector and the characteristics of the design parameters were analyzed. Furthermore, the prototypes of the proposed collector were built and tested at a state-of-the-art solar simulator facility to evaluate its actual performance. The inclusion of CNT improved significantly the properties of the polymer absorber. The key design parameters and their effects on the thermal performance were identified via the heat transfer analysis. Based on the experimental and analytical results, the cost-effective polymer-CNT solar collector, which achieved a high thermal efficiency similar to that of a conventional glazed flat plate solar panel, was successfully developed.
Resumo:
Since the 1970s, there has been growing academic interest in children and young people living in state care and, more recently, in the lives of disabled children. However, there has been little attention on the lives of disabled children who are looked after by the state. This paper compares and critiques what is known about the numbers of disabled children who are looked after in England, Northern Ireland, Scotland and Wales. We discuss the conceptual and methodological limitations of systematically collecting data on disabled children in state care across the United Kingdom. We argue that to ensure the rights of disabled children in state care are identified, acknowledged and upheld, ‘being counted’ is a fundamental first step.