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Current Progress of Activities at EU-SOLARIS ERIC: The European Research Infrastructure Consortium for CSP Technologies
No full textABSTRACT: An ERIC, established by a decision of the European Commission, is a legal entity possessing legal personality and full legal capacity acknowledged across all EU Member States. Its primary role is to establish and operate a research infrastructure on a non-economic basis. Under the initiative of Spain, France, Germany, and Cyprus as Members, with Portugal as an Observer, a European Research Infrastructure Consortium (ERIC) has been formed. This consortium, named "European Solar Research Infrastructure for Concentrated Solar Power" (EU-SOLARIS ERIC) is established in accordance with Council Regulation (EC) No. 723/2009 of 25 June 2009. The establishment of an ERIC was sanctioned by the European Commission, as evidenced in Commission Implementing Decision (EU) 2022/2297 of 19 October 2022 [1]. The inaugural assembly of the EU-SOLARIS ERIC took place at the CIEMAT Headquarters in Madrid on 12th January 2023. During this gathering, the General Assembly was officially convened, and the Statutes along with other governing documents were formally endorsed. At the time of composing this document, negotiations for the accession of three additional countries—Greece, Turkey, and Italy—are underway. This paper summarizes the R&D activities carried out during this first year of the ERIC, particularly, we describe the new projects achieved
Determination of reflectance of interest from limited state-of-the-art solar reflector field soiling measurements
No full textABSTRACT: In concentrated solar thermal technologies, plant operators usually monitor the soiling of their solar field with handheld reflectometers. These measurements can be used for yield calculations and to adapt cleaning strategies: if the reflectometer reading falls below an empirically established threshold, the solar field should be cleaned. There are several commercial reflectometers available for this purpose, but all of them measure at different combinations of wavelength, acceptance angle or incidence angle. It is the purpose of this study to bring the readings from all main commercial reflectometers to the same representative value, enabling their comparison with one another and the translation of these readings into a meaningful reflectance parameter. Thus, different handheld reflectometers are correlated with a laboratory reflectometer, capable of measuring in the whole solar spectral region, covering a wide range of incidence and acceptance angles. The most significant parameter is the near-specular solar-weighted reflectance, measured at the typical incidence and acceptance angles for a given plant, as it is the most precise parameter to describe the reflected energy from the solar field. The correlations for all included reflectometers, show highly linear correlations over a wide range of soiling levels with low deviations. Consequently, the correlations presented herein enable the plant operators at the studied site to compute the near-specular solar-weighted reflectance from their reflectometer readings. and, with that, increase the significance of the measurements without collecting any additional data. The work also establishes a detailed procedure to derive this type of correlations at any site of interest.SolarPACES, a Technology Collaboration Programme (TCP) of the International Energy Agency (IEA)
Computation of Hydrodynamic Coefficients for Submerged Spheres: A Comprehensive Analysis
No full textABSTRACT: Hydrodynamic coefficients are essential parameters in fluid mechanics that serve to quantify the complex interaction between a submerged body and the surrounding fluid . Specifically in the context of submerged spheres, these coefficients provide a measure of the forces and moments exerted by the fluid on the sphere, or conversely, the resistance the sphere encounters as it moves through the fluid . Understanding and accurately determining these coefficients is paramount for a wide range of applications, including the design and control of underwater vehicles, the analysis of offshore structures, and the prediction of the behavior of marine organisms. The accurate prediction of wave loads on submerged structures also relies heavily on the evaluation of these coefficients. The significance of hydrodynamic coefficients lies in their ability to simplify the complex physics of fluid-structure interaction into manageable parameters. For instance, the added mass coefficient reflects the inertia of the fluid that is accelerated along with the moving sphere, effectively increasing the sphere's apparent mass. This phenomenon is critical in dynamic analyses, as the inertial forces are directly influenced by this added mass. Similarly, the drag coefficient quantifies the resistance force that opposes the sphere's motion, a force primarily attributed to viscous effects and the pressure distribution around the body. In certain flow regimes, particularly involving non-uniform flow fields such as those induced by waves or in the presence of rotation, a lift coefficient may also become relevant, representing a force acting perpendicular to the direction of motion. The accurate determination of these coefficients, which can be linear or nonlinear depending on the complexity of the fluid-structure interaction, is a crucial step in the design and analysis of any system involving submerged spheres. The interaction between a submerged sphere and the surrounding fluid exemplifies a fundamental fluid-structure interaction problem. When a solid object like a sphere is placed in the path of a fluid, the fluid exerts pressure and viscous forces on the sphere's surface, potentially leading to its motion or deformation. Conversely, the presence and motion of the sphere alter the flow field of the fluid. Hydrodynamic coefficients serve as the critical link in understanding this bidirectional influence, allowing engineers and researchers to predict the dynamic response of the sphere to fluid forces and the impact of the sphere's motion on the fluid environment. For example, in the context of underwater explosions, the structural response of a submerged body significantly affects the dynamics of the explosion bubble, highlighting the intricate nature of fluid-structure interaction where hydrodynamic coefficients play a vital role
Protection of Steel Structures against Fire and Corrosion by Paint Coatings: A comparative study
No full textABSTRACT: Steel structural systems in modular construction must be protected against corrosion and fire exposure. The durability of both protective properties plays a key role in ensuring long-term service life and minimizing maintenance costs. The present work aims to validate anticorrosive protection systems for steel structures, with and without fire protection properties, evaluating degradation mechanisms and assessing the compatibility of intumescent layers with anticor-rosive coatings, in terms of their impact on corrosion resistance and fire protec-tion properties
Satellite-based offshore wind data close to the coast: comparison with onshore meteorological mast records and microscale CFD simulations
No full textABSTRACT: Satellite observation of environmental phenomena is becoming increasingly accurate, complementing pre-existing measurement techniques. In this work, the offshore wind field recorded by Sentinel-1 on February 6th, 2021, close to the Southwestern Iceland coast is compared with the anemometric measurements provided by a relatively dense network of weather stations in the Reykjanes peninsula and microscale CFD simulations that use the Hvassahraun weather station data to approximate wind velocity and direction in offshore locations. The three methodologies show a good agreement in the 10-minute velocity magnitudes for the set of considered offshore locations, while the 10-minute mean wind direction shows certain scattering, although with a consistent prevalence of Eastern wind directions, in agreement with the anemometric data. The results show obvious complementarities among the three approaches, suggesting further studies to improve accuracy, especially for capturing local effects impacting wind magnitude and directionality.COST Action CA20109 Modenerlands, supported by COST (European Cooperation in Science and Technology
Evaluating the role of physical mechanisms as possible triggers for turbidity currents in a deep ocean seamount
No full textABSTRACT: Turbidity currents on continental margins are often attributed to cyclic climate variability and sea-level change, while the causes of deep ocean turbidites are as yet to be tested. The Atlantic Iberian margin provides a unique setting to contrast deep ocean and continental environments, including depression features that further protect from resuspension and erosion by along-slope bottom currents. We present records of low-frequency, non-periodic, climate-independent turbidites from three deep cores covering up to 426,000 years in the Tore seamounts area. By evaluating a range of physical oceanographic mechanisms, the breaking of internal waves and mesoscale Mediterranean-eddies against unstable slopes in the seamounts area arises as the most likely triggers that precondition the recurrence pattern of the observed deep ocean turbidites
Oportunidades e desafios num distrito mineiro de classe mundial, a Faixa Piritosa Ibérica
No full textABSTRACT: A summary is made on the exploration work carried out in the Iberian Pyrite Belt (IPB) and an attempt is made to describe the evolution of the exploration methods and strategies applied in the field which led to the discovery of the main deposits. Finally, a reference is made to the good potential for new discoveries in the IPB, giving clues about new exploration models to be pursued. Being undoubtedly a world-class metallogenic province, the IPB naturally deserves a special mention regarding the mining history and on the evolution of the exploration techniques, adjusted to the new paradigms, namely in the need to search at ever greater depths. The most recent cases of successful new discoveries in the IPB are described, largely resulting from the refining of geological, geophysical and geochemical prospecting methodologies, and clues that are expected to lead to the discovery of new concealed deposits are equated.RESUMO: Faz-se uma síntese dos trabalhos de prospeção realizados na Faixa Piritosa Ibérica (FPI) e procura-se descrever a evolução das metodologias e estratégias de exploração aplicadas no terreno que conduziram à descoberta dos principais jazigos. Por fim, é feita referência ao elevado potencial de novas descobertas no IPB, dando pistas sobre novos modelos e estratégias a desenvolver. Sendo inquestionavelmente uma província metalogénica de classe mundial, a FPI merece naturalmente uma referência especial no que respeita à história mineira e à evolução das técnicas de investigação, ajustadas aos novos paradigmas, nomeadamente na necessidade de prospeção a profundidades cada vez maiores. Discutem-se os casos mais recentes de novas descobertas bem sucedidas na IPB, resultantes, em grande parte, do refinamento de metodologias de prospeção geológica, geofísica e geoquímica, sendo traçadas novas pistas, que se espera, levem à descoberta de novos depósitos ocultos
The old central igneous complexes of Sal, Boa Vista and Maio islands: Implications for 17 Ma of isotopic evolution of the Cape Verde archipelago
No full textABSTRACT: The central igneous complexes of the easternmost islands (Sal, Boa Vista and Maio) preserve some of the most ancient outcropping rocks of the Cape Verde (CV) archipelago. These Early to Middle Miocene (about 25 to 12 Ma) complexes show marked isotopic differences between mafic rocks from the northern (Sal and Boa Vista) and the southern Maio Island, the latter showing lower 143Nd/144Nd, 206Pb/204Pb, 207Pb/204Pb, and higher 87Sr/86Sr ratios. The main mantle plume composition beneath Cape Verde is here considered to be dominated by the FOZO component. Our data supports previous models suggesting the incorporation to plume components of minor DMM mantle sources in the northern CV island alignment, whereas mixing with the EM1 pole is prevalent on the southern CV islands. These isotopic differences are evident since the early stages of Cape Verde magmatism. The Late Miocene to Holocene time period (7 to 1.7 Ma) is characterized by the irruption of silica-undersaturated and carbonatite magmas with a relatively homogeneous isotopic composition and highly radiogenic Pb signatures (206Pb/204Pb up to 20.6 in carbonatitic rocks and 20.2 in silicate rocks) throughout most of the Cape Verde archipelago. During this transitional stage, the input of this new HIMU mantle component overprinted the previous mixing of the main FOZO plume component with shallow mantle members (DMM, EM1) of minor contribution
Nature conservation, land use planning and exploitation of ornamental stones: the case study of Cabeça Veada (Portugal)
No full textABSTRACT: Cabeça Veada is the name of a relatively small exploitation cluster for ornamental limestones occupying an area of 98 ha in the Portuguese Natural Park of Serra de Aire e Candeeiros, which is also a Natura 2000 Network protected area. Supported by comprehensive geological, mining and environmental studies, a specific methodology was developed in order to address the compatibility between the long term sustainability of this industry with the preservation of existing protected natural values. The obtained land use map should allow the Cabeça Veada mineral resources to be adequately included in the municipal land use planning process.info:eu-repo/semantics/publishedVersio