264 research outputs found
Estudio experimental sobre el comportamiento térmico de un nuevo tipo de techo-estanque para el enfriamiento pasivo en clima húmedo
En este trabajo, una nueva tipología de techo-estanque metálico, basado en el enfriamiento evaporativo indirecto, que incluye masa térmica confinada, se evalúa experimentalmente. Cinco sistemas de enfriamiento pasivo se han estudiado con este dispositivo experimental. Se analizan sus temperaturas características con el propósito de determinar en cada caso, su potencial de enfriamiento, así como, la influencia de la masa térmica en su comportamiento térmico. Entre las técnicas de enfriamiento pasivo aplicadas se encuentran el enfriamiento evaporativo indirecto (EEI) y el enfriamiento radiativo nocturno (ER). El sistema donde se combina masa térmica con enfriamiento evaporativo indirecto en el dispositivo experimental presenta una elevada eficiencia de enfriamiento; su valor aumenta a medida que las condiciones son más extremas. Un potencial de enfriamiento aun mayor se consigue al agregar al sistema anterior enfriamiento radiativo
geo climatic applicability of direct evaporative cooling in italy
This chapter focuses on the climatic applicability of passive direct (downdraught) evaporative cooling (PDEC) techniques in the provincial capital cities of Italy. First, a PDEC potentiality map was produced using a previously developed method based on three variables: wet bulb depression, summer comfort air temperature threshold (25 °C) and cooling degree hours (CDHs). Second, an applicability map was produced by comparing the PDEC potentiality map to the local cooling energy demand. Third, a new method is presented including a calculation of the residual local cooling energy demand, i.e. residual CDH, related to air treatment by direct evaporative cooling. These residual CDH values were calculated considering different step-wise increasing outlet temperatures (WBT; WBT + 1 °C; …; WBT + 5 °C) as a function of the covered amount of wet bulb depression. Finally, three cities chosen as being representative of their respective Italian climatic macro-zones were selected in order to assess in greater detail the yearly variation of CDH aimed at supporting specific design strategies for ventilative passive cooling solutions
Assembling sustainable ideas: The construction process of the proposal SMLsystem at the Solar Decathlon Europe 2012
[EN] The innovation of the construction process in SMLsystem lies in an evolution of the way of thinking the sustainable architecture. The key is that SMLsystem proposal is not constructed but is assembled. This way, it is designed with prefabricated and industrialized elements which allow themselves to connect as in a plug and play process in order to reduce the risks and save time and costs consequently. About that, the study and design of the junction has been another interesting issue to solve the assembly of the modules, focusing on factors like the isolation and the rainwater always present. In addition this proposal shows a new way in the use of wood as a structural material, as a building enclosure and as a dynamic system of solar protection, all of them as a result of the combination of various premises inherent to the concept of the project like the respect for the environment, recycling or sustainability and, of course, with an absolute integration with the architectural design. This way, the complete development of SMLsystem has had the capacity of defining a global project which reflects the primal ideas: design, sustainability, modularity, flexibility and prefabrication. © 2014 Elsevier B.V. All rights reserved.The research reflected in this paper has been possible thanks to the support of the CEU Cardenal Herrera University and of many companies who have contributed to the realization of housing SMLsystem. This effort and commitment to research are translated into a competitive, quality teaching and research staff improvement and also as a result to the University advance.Serra Soriano, B.; Verdejo Gimeno, P.; Diaz Segura, AL.; Meri De La Maza, RM. (2014). Assembling sustainable ideas: The construction process of the proposal SMLsystem at the Solar Decathlon Europe 2012. Energy and Buildings. 83:186-194. doi:10.1016/j.enbuild.2014.03.075S1861948
The effect of temperature, gradient and load carriage on oxygen consumption, posture and gait characteristics
Purpose The purpose of this experiment was to evaluate the effect of load carriage in a range of temperatures to establish the interaction between cold exposure, the magnitude of change from unloaded to loaded walking and gradient. Methods Eleven participants (19-27 years) provided written informed consent before performing six randomly ordered walking trials in six temperatures (20°C, 10°C, 5°C, 0°C, -5°C and -10°C). Trials involved two unloaded walking bouts before and after loaded walking (18.2 kg) at 4 km.hr⁻¹, on 0% and 10% gradients in 4 minute bouts. Results The change in absolute oxygen consumption (V̇O₂) from the first unloaded bout to loaded walking was similar across all six temperatures. When repeating the second unloaded bout, V̇O₂ at both -5°C and-10°C was greater compared to the first. At -10°C, V̇O₂ was increased from 1.60 ± 0.30 L.min⁻¹ to 1.89 ± 0.51 L.min⁻¹. Regardless of temperature, gradient had a greater effect on V̇O₂ and heart rate (HR) than backpack load. HR was unaffected by temperature. Stride length (SL) decreased with decreasing temperature but trunk forward lean was greater during cold exposure. Conclusion Decreased ambient temperature did not influence the magnitude of change in V̇O₂ from unloaded to loaded walking. However, in cold temperatures, V̇O₂ was significantly higher than in warm conditions. The increased V̇O₂ in colder temperatures at the same exercise intensity is predicted to ultimately lead to earlier onset of fatigue and cessation of exercise. These results highlight the need to consider both appropriate clothing and fitness during cold exposure
Otimização multiobjetivo das dimensões dos ambientes de uma residência unifamiliar baseada em simulação energética e estrutural
Resumo O desenvolvimento da tecnologia computacional nas últimas décadas levou a otimização associada à parametrização a possibilitar o desenvolvimento de projetos de melhor desempenho, com ou sem integração com a simulação. O intuito deste trabalho foi aplicar a otimização baseada em simulação na forma de uma edificação residencial unifamiliar com o objetivo de encontrar a composição que apresentasse o melhor desempenho térmico com o menor custo dos materiais construtivos, considerando-se restrições estruturais. Foram utilizados os programas Rhinoceros e Energy Plus, além de plug-ins para modelagem paramétrica, o intercâmbio de informações entre os programas e a condução da otimização. Foram realizadas duas simulações, a primeira considerando os custos dos componentes construtivos e os graus-hora de aquecimento e resfriamento combinados e a segunda considerando os custos e graus-hora de aquecimento, que produziu resultados mais relevantes. Dois casos de cada solução de Pareto foram selecionados para análise, dentre 19,8 mil e 27,4 mil casos obtidos com uso de algoritmos evolucionários. Apesar das limitações de algumas das ferramentas, foi verificado um grande potencial de aplicação deste método no desenvolvimento de projetos arquitetônicos
Potencial de economia de energia elétrica através do uso da luz natural e da ventilação híbrida em edifícios comerciais em Florianópolis
O objetivo deste estudo é estimar o potencial de economia de energia elétrica com o uso da luz natural integrada ao sistema de iluminação artificial e a utilização da ventilação híbrida em edifícios comerciais localizados em Florianópolis, SC. O trabalho foi baseado em simulações computacionais nos programas EnergyPlus e Daysim. Foram simulados modelos de ambientes de edificações comerciais, com três geometrias, três dimensões de sala por geometria, dez áreas de janela por modelo e quatro orientações. Os modelos foram examinados por meio de quatro estudos de caso. No Caso 1 (referência), a edificação opera com sistemas de iluminação e de condicionamento artificiais; no Caso 2, ocorre a integração da iluminação natural com a artificial, com condicionamento artificial; já no Caso 3, utilizam-se a ventilação híbrida e a iluminação artificial; no Caso 4, adotam-se a iluminação natural integrada com a artificial e a ventilação híbrida. Os consumos de eletricidade do Caso 1 foram comparados com os demais casos. Assim, foi estimado o potencial de economia de energia elétrica gerado pelo uso da luz natural e ventilação híbrida. Conclui-se que a utilização da iluminação natural e da ventilação híbrida em edificações comerciais localizadas em Florianópolis apresenta potencial de economia de energia elétrica de até 64,9% e que essas estratégias podem ser utilizadas para aumentar a eficiência energética desse tipo de edificação
Estudo de conforto em espaços abertos em região de clima temperado: o caso de Glasgow, Reino Unido
O estudo da sensação de conforto térmico em espaços abertos deve ser entendido como primordial para o planejamento climaticamente adequado de áreas urbanas. Através do aumento da atratividade das àreas abertas e do incentivo às atividades ao ar livre, o planejamento urbano norteado do pelas preferências térmicas da população torna-se um agente facilitador do uso desses espaços. O presente trabalho analisa a sensação térmica de moradores de Glasgow, Reino Unido, localizada em região temperada, comparando respostas obtidas por meio de entrevistas estruturadas a índices utilizados pela meteorologia (Wind Chill e THSW) e em estudos de conforto (PET e PMV). Os dados foram coletados em 19 campanhas de monitoramento, no período do inverno ao verão de 2011. Para a coleta de dados, foi utilizada uma estação Davis Vantage Pro2, contendo sensores de temperatura e umidade relativa, anemômetro e piranômetro. Foi confeccionado um termômetro de globo, utilizado para obtenção da temperatura radiante média (TRM), equipado com um data logger (Tinytag-TGP-4500). Os resultados indicam que os índices THSW e PET foram os que mais se aproximaram da resposta térmica dos entrevistados, podendo ser aplicados no entendimento das condições do clima na cidade e entorno de Glasgow
Comportamento térmico de fechamentos em alvenaria estrutural para a Zona Bioclimática 2 brasileira
A multi-modal network approach to model public transport accessibility impacts of bicycle-train integration policies
In the Netherlands, the bicycle plays an important in station access and, to a lesser extent, in station egress. There is however fairly little knowledge in the potential effects of bicycle-train integration policies. The aim of this paper is to examine the impacts of bicycle-train integration policies on train ridership and job accessibility for public transport users.MethodsWe extended the Dutch National Transport Model (NVM) by implementing a detailed bicycle network linked to the public transport network, access/egress mode combinations and station specific access and egress penalties by mode and station type derived from a stated choice survey. Furthermore, the effects of several bicycletrain integration policy scenarios were examined for a case study for Randstad South, in the Netherlands, comprising a dense train network with 54 train stations.ConclusionsOur analysis shows that improving the quality of bicycle routes and parking can substantially increase train ridership and potential job accessibility for train users. Large and medium stations are more sensitive to improvements in bicycle-train integration policies, while small stations are more sensitive to improvements in the train level of service
Is radical innovation in architecture crucial to sustainability? Lessons from three Scottish contemporary buildings
Radical innovation is largely recognised as a medium for advancement, a source of growth for economies, and a trigger for progress in different economic sectors. Often, this type of innovation is identified with technological advancements, disruptive phenomena and the creation of new systems and dynamics. Yet, within the context of a changing world, in which principles of economic, environmental and social sustainability are largely adopted as common objectives, a reflection on the type of progress and the need for radical innovation is necessary with the aim of informing on their impacts and effectiveness. This work presents an analysis of a number of contemporary Scottish architectural designs, developed under the aegis of sustainability principles, and explores the types of sustainable innovations introduced and the results achieved by analyzing the type of design change that triggered specific sustainable results, demonstrating alternative innovation strategies, other than the radical one. This analysis provides a basis for discussion on the need for radical innovation in the context of sustainable architecture and explores the role of other types of innovation against the results achieved. This discussion could contribute to a better understanding of the current state of practice in architectural design, as well as in policy making in regard to the design and management of the future built environment
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