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Abstract The OECD/NEA Sandia Fuel Project provided unique thermal-hydraulic experimental data associated with Spent Fuel Pool (SFP) complete drain down. The study conducted at Sandia National Laboratories (SNL) was successfully completed (July 2009 to February 2013). The accident conditions of interest for the SFP were simulated in a full scale prototypic fashion (electrically heated, prototypic assemblies in a prototypic SFP rack) so that the experimental results closely represent actual fuel assembly responses. A major impetus for this work was to facilitate severe accident code validation and to reduce modeling uncertainties within the codes. Phase I focused on axial heating and burn propagation in a single PWR 17 × 17 assembly (i.e. “hot neighbors” configuration). Phase II addressed axial and radial heating and zirconium fire propagation including effects of fuel rod ballooning in a 1 × 4 assembly configuration (i.e. single, hot center assembly and four, “cooler neighbors”). This paper summarizes the comparative analysis regarding the final destructive ignition test of the phase I of the project. The objective of the benchmark is to evaluate and compare the predictive capabilities of computer codes concerning the ignition testing of PWR fuel assemblies. Nine institutions from eight different countries were involved in the benchmark calculations. The time to ignition and the maximum temperature are adequately captured by the calculations. It is believed that the benchmark constitutes an enlargement of the validation range for the codes to the conditions tested, thus enhancing the code applicability to other fuel assembly designs and configurations. The comparison of lumped parameter and CFD computer codes represents a further valuable achievement.

Abstract Building-integrated photovoltaic (BIPV) panels are emerging as a useful technology for helping to achieve net-zero energy buildings. At this time, the main drawback with BIPV systems is the cost per kilowatt per hour of electricity generated. Besides cheaper production of photovoltaic panels, increases in their efficiency can be obtained by reducing panel temperatures. This is often achieved by adding a cavity beneath the panels to allow ventilation of the rear of the panel. However, the details of airflow in the cavity and the effect on cooling have not been rigorously researched. Life-time enhancement against degradation is also an effective technique to reduce the cost of electricity generated. Moisture ingress and thermal stresses are among the primary reasons for degradation of BIPVs; these processes are directly affected by air and moisture flow around the panels. The surface temperature thermography and airflow observations performed in this work helps to understand the transport mechanisms above and below the panels. For this purpose, a novel setup was developed consisting of a building model with a mock BIPV panel plus a solar simulator placed inside an atmospheric wind tunnel. Particle image velocimetry (PIV) and infra-red thermography were performed to simultaneously monitor the surface temperature and airflow above and below the panel. The study clearly shows how the accelerated airflow within the cavity increases the heat exchange between the PV and airflow and consequently reduces the PV temperature. It is also shown that the stepped open arrangement of panels is more effective in reducing the temperature comparing to a flat arrangement. This arrangement also has a better resistant against the air and moisture ingress.

Consistent climate data and reliable sizing methods are fundamental for designing Technical Building Systems. This paper addresses both these aspects with reference to the Italian context analyzing 108 different locations. Regarding the climate data, a quality analysis through the application of rules and filters was performed on the locations. The results showed good data quality, with most sites having high percentages of usable material, although highlighting recursive criticalities in the detection of humidity and wind speed parameters. Regarding the sizing methods, a sensitivity analysis was carried on for the European standard EN ISO 15927-2 to evaluate its performances in selecting the Cooling Design Days in the 108 locations. The analysis highlighted great differences in terms of chosen Design Days when using different climatic parameters, showing at the same time a negligible influence of the wind speed on the selection process. Furthermore, a sizing process for a test building applied to the 108 locations was carried on by using the Cooling Design Days. The results highlighted that the Design Days obtained through the EN ISO method often give counterintuitive sizing outputs, even obtaining higher required powers for lower risk levels, the opposite of how it should be. This implies that a designer should be very careful in evaluating which parameters to use in the Design Day selection and if the output sizing powers obtained through them are reliable for its particular sizing process.

This study is based on assessing fecal indicator bacteria contamination along meteorological, hydrological and physical-chemical variables after high rainy events during the summer period. The study focused on four different coastal sites in the western and eastern Adriatic coast characterized by various geomorphological and hydrological features, levels of urbanization and anthropogenic pressures, with the aim of finding appropriate and effective solutions to ensure the safety and sustainability of tourism and public health. Detailed in-situ survey revealed a wide range of fecal indicator bacterial (FIB) across the different river mouths with concentrations of E. coli ranging from 165 to 6700 CFU 100 mL-1. It was found that nitrogen compounds track microbial load and acted as tracers for fecal contaminants. Further, a modelling tool was also used to analyze the spatial and temporal distribution of fecal pollution at these coastal sites. The integrated monitoring through high frequent survey in river waters and modeling framework allowed for the estimation of fecal indicator bacterial load at the river mouth and examination of fecal pollutant dispersion in recreational waters, considering different scenarios of fecal dispersion along the coast. This study formed the basis of a robust decision support system aimed at improving the management of recreational areas and ensuring the protection of water bodies through efficient management of bathing areas.

Abstract Sustainability is an important and difficult consideration for the stakeholders/decision-makers when planning a biofuel supply network. In this paper, a Mixed-Integer Non-linear Programming (MINLP) model was developed with the aim to help the stakeholders/decision-maker to select the most sustainable design. In the proposed model, the emergy sustainability index of the whole biodiesel supply networks in a life cycle perspective is employed as the measure of the sustainability, and multiple feedstocks, multiple transport modes, multiple regions for biodiesel production and multiple distribution centers can be considered. After describing the process and mathematic framework of the model, an illustrative case was studied and demonstrated that the proposed methodology is feasible for finding the most sustainable design and planning of biodiesel supply chains.

There is general agreement that migration is likely to play an increasingly crucial role in adaptation to climate change. However, as this paper argues, technocratic and de-politicised discourses of climate change have often been invoked to conceal underlying political agendas in which environmental concerns are drawn upon to justify unfavourable government policies of mobility and resettlement. This paper examines the politics of climate change discourse through an analysis of resettlement policies in the Maldives where the government is proposing the consolidation of a population dispersed over 200 islands onto 10–15 islands. However, this initiative is not new. The government has long thought it economically, rather than environmentally, unsustainable to provideservices and resources to a dispersed population, and has for many years muted policies to move people in order to reduce the costs on government. Today, the same initiatives are gaining renewed leverage by being couched in environmental terms. Without denying the realities of the negative consequences of climate change for small island states, this article explores the political imperativesthat are influencing discussions of climate change and migration, and specifically how environmental discourses are being mobilised to re-introduce previously unpopular resettlement and migration policies.