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A new concept of flat plate solar collector (FPC) has been numerically studied for optimization purposes from an energetic and exergetic points of view. The highly efficient results have been achieved by adding transparent insulation materials (TIM) made of plastic and aerogel-silica in the cover. The optimum solution has been prototyped and successfully tested. The numerical simulation and the corresponding analysis are performed with a previously developed numerical simulation tool based on an in-house software platform (NEST). An optimization design has been done using this numerical simulation tool objected to higher performance at the (¿in -¿amb)/ ¿ ¿ > 0.074 range, and a new prototype is fabricated with low-cost materials found in the workshop. The final results are compared with previous prototypes that could collect between 2.5 and 1.4 times higher than standard collectors in summer and autumn, respectively. The new prototype has higher performance at (¿in -¿amb)/ ¿ ¿ > 0.074, which makes it competitive in a high-temperature range. Moreover, with the new layer of aerogel-silica, additional protection against overheating is achieved, as the temperatures of the plastic TIM are limited. The new prototype has higher energetic and exergetic efficiency at high-temperature areas, and the inlet temperature at optimized working conditions is higher than the previous prototype. Finally, the energy efficiency at (¿in -¿amb)/ ¿ ¿ = 0.08 could reach 55% and exergetic efficiency 8%. The manufacturing cost of the FPC prototype with TIM and aerogel-silica is about 160 euros per m2., This work has been financially supported by the SUDOKET – SOE2/P1/E0677 project under the Interreg-Sudoe program. J. Zheng holds a China Scholarship Council Studentship with the Polytechnical University of Catalonia, Spain., Peer Reviewed, Postprint (published version)

In the Alto Balsas sub-basin in the states of Puebla and Tlaxcala, agricultural soils are irrigated with wastewater that has accumulated heavy metals. These compounds represent a health risk because they can be ingested, inhaled or absorbed and cause cancerous and non-cancerous diseases. The aim of this research was to determine the content of Cd, Pb, Cr and As in the agricultural soils of four irrigated areas: Tepetitla de Lardizabal, Nativitas, Santa Isabel Tetlatlahuca and Tecamachalco; asessments were made using an Inductively Coupled Plasma Optical Emission spectroscop (ICP-OES). The health risk for men, women and children was calculated using equations from the Unites Estates Environmental Protection Agency (USEPA) and the extent of impact of soil contamination with heavy metals was calculated in terms of percentage by spatial analysis. Apparently, adults are at greatest risk and Cd and Cr are the most dangerous metals for the population. The method of exposure that represents the greatest risk for children was oral but among adults it was dermal. Cancer risk was greatest among adults, in descending order Cd>As>Cr>Pb. Regarding the aspect of affectation, 51 municipalities of the Alto Balsas and Valsequillo canal sub-basin are affected, where Cd, Pb and Cr were found in 100% and As in 99%, of the total surface., En la subcuenca del Alto Balsas en los estados de Puebla y Tlaxcala, los suelos agrícolas son irrigados con aguas residuales que han acumulado metales pesados. Estos compuestos representan un riesgo para la salud, debido a que pueden ser ingeridos, inhalados o absorbidos y generar enfermedades cancerígenas y no cancerígenas. El objetivo de la investigación fue determinar el contenido de Cd, Pb, Cr y As en suelos agrícolas de cuatro zonas irrigadas: Tepetitla de Lardizabal, Nativitas, Santa Isabel Tetlatlahuca y Tecamachalco, las determina­ciones fueron realizadas por medio de un ICP - OES. Se calculó el riesgo de salud para hombres, mujeres y niños utilizando las ecuaciones de la Unites Estates Enviromental Protection Agency (USEPA) y se calculó en términos porcentuales, el área de alcance de la contaminación de los suelos con metales pesados por medio de un análisis espacial. Se encontró que los mayores riesgos son para los adultos y fueron el Cd y Cr los metales más peligrosos para la población. La vía de exposición que representa el mayor riesgo fue oral en los niños y en adultos la vía dérmica. El riesgo de cáncer fue mayor en adultos, con orden descendente Cd>As> Cr>Pb. En cuanto a la dimensión de la afectación, 51 municipios de la subcuenca del Alto Balsas y canal de Valsequillo son afectados, donde el Cd, Pb y Cr fueron encontrados en todos, el As en 99% de la superficie total.

This thesis explores the numerical resolution of mass, momentum, and energy conservation equations, with a focus on their application in absorption and adsorption refrigeration systems. It begins with establishing the fundamentals of computational fluid dynamics, with classic cases examined and validated through custom C++ code. The research then moves to practical case study: falling film heat transfer, a key process in absorption and absorption refrigeration. The simulation of liquid ethylene glycol film flow over a vertical plate is performed using the open foam solver interFoam. The simulation results are validated against both experimental and numerical data, and boundary conditions are optimized for accuracy. Additionally, a new solver, interTempFoam, is introduced to incorporate the temperature transport equation. The heat transfer phenomenon occurring in falling film is analysed and assessed.

The operation of a solar-driven H2O-LiBr Absorption Chiller (AbC) is subjected to various limitations regarding its ability to satisfy efficiently the required cooling demand while avoiding certain internal conditions, such as H2O-LiBr solution crystallization and water freezing. These circumstances would lead to problematic situations and jeopardize the continuous operation of the system. Thus, the development of accurate control strategies is an issue of interest. A new operational control strategy approach is introduced and tested through simulation studies, by employing a transient model of the entire solar cooling application. A prototype under development is used for the parametrization of the direct air-cooled AbC model used in the simulations. The developed control strategy aims to minimize the electrical consumption of the auxiliary components of the AbC (i.e., fan, pumps) during the partial load operation period, by using a fuzzy logic interference rule for determining the cooling capacity demand and then applying an optimization algorithm for determining the velocity of the auxiliary components. Within the proposed control strategy, a fast-calculation model is embedded, which predicts the chiller’s capacity under variable external conditions and partial load operation. The electrical COP is increased up to 2.2 times with respect to a baseline case, based on a basic two-step control strategy, while allowing the chiller to operate smoother, minimizing the crystallization and freezing risk., This project has received funding from SOLAR-ERA.NET Cofund 2 Joint Call undertaking under the European Union’s Horizon 2020 research and innovation program (ECOSUN project) . During the elaboration of the work, G. Papakokkinos held a Margarita Salas Grant of the Spanish Government and J. Zheng a China Scholarship Council Studentship with the Polytechnical University of Catalonia., Peer Reviewed, Postprint (published version)

Esta tabla referencia y recopila todos los elementos materiales del Edificio de los Betilos empleados en la realización del presente estudio. Se han excluído todas las piezas pertenecientes a niveles superiores. El recuento de los materiales se ha agrupado por Fases y por Estancias. Se indica ND (no data) cuando alguna de las UEs no puede adscribirse a alguna de las fases, o porque pertenecen a una campaña de excavación anterior al 2017, lo que imposibilita su reconstrucción estratigráfica.

[ES] El siguiente artículo expone una revisión del registro arqueológico de la necrópolis de Cadabarcos (Mañón, A Coruña). Este yacimiento, excavado en la década de los 40 por Federico Maciñeira e identificado como una necrópolis “galaicorromana”, podría presentar una cronología bastante más tardía respecto a lo habitual en los enterramientos con fosas de cremación. En el siguiente trabajo, se expone una profunda revisión de las características de este yacimiento, explorando su contexto de intervención, las dinámicas históricas de la región, los hallazgos documentados y las características de la zona intervenida, con la intención de verificar su adscripción funcional, cronológica y cultural. Atendiendo a los resultados, se realiza un análisis contextual del yacimiento, relacionándolo con las principales dinámicas de enterramiento del Noroeste penisular. Se analizan las prácticas y tradiciones funerarias desde el Alto Imperio hasta los inicios de la Antigüedad Tardía, estableciendo una comparativa entre distintas dinámicas regionales, y se propone una revisión cronológica y territorial de la cremación como práctica funeraria., [GL] O siguiente artículo expón unha revisión do rexistro arqueolóxico da necrópole de Cadabarcos (Mañón, A Coruña). Este xacemento, escavado nos anos 40 por Federico Maciñeira e idenntificado como unha necrópole “galaicorromana”, podería presentar unha cronoloxía bastante máis tardía do habitual para os xacementos con foxas de cremación. No seguinte traballo, exponse unha profunda revisión das características deste xacemento, explorando o seu contexto de intervención, as dinámicas históricas da rexión, os achados documentados e as características da zona intervida, co obxectivo de verificar a súa adscrición funcional, cronolóxica e cultural. Atendendo aos resultados, realízase unha análise contextua, do xacemento, relacionándoo coas principais dinámicas de enterramento do Noroeste peninsular. Analízanse as prácticas e tradicións principais dende o Alto Imperio ata o comezo da Antigüidade Tardía, establecendo unha comparativa entre distintas dinámicas rexionais, e proponse unha revisión cronolóxica e territorial da cremación como práctica funeraria., [EN] This paper presents a review of the archaeological record of the necropolis of Cadabarcos (Mañón, A Coruña). This site was excavated in the 1940s by Federico Maciñeira and identified as a “Galaicorroman necropolis”; however, its material record seems to reveal much later chronologies with relation to the usual examples of burial sites with cremation pits. In this work, a complete review of the characteristics of this site is presented, exploring its context of intervention, the historical dynamics of the region, the archaeological findings, and the characteristics of the intervened area. The main aim of this approach is to assess the characteristics of its sequence of occupation. In line with these results, an analysis of the site is proposed, focusing on the framework of burial patterns in the Northwest of the Iberian Peninsula. Funerary practices and traditions from the High Empire to the beginning of the Late Antiquity period are analysed, drawing a comparison between different regional trends, and suggesting a chronological review of cremation as a burial practice.