99 research outputs found

    Evaluating energy recovery potential in Murcia's water supply system

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    Murcia is the 7th most populated city in Spain. Its water supply system is extensively monitored through a large number of pressure gauges and flow meters. Murcia’s water supply network is fed from distribution reservoirs at enough elevation to avoid needing pumping stations for most of the city districts. Hydraulic resources have been evaluated throughout the water supply system. Besides the pressure reducing valves, where the assessment is quite straight forward [1], District Metered Areas (DMA) inlets have been evaluated. In these areas despite the hydraulic resources are not as great as in pressure reducing valves locations, their location is quite convenient. Actually, these positions are located inside the city, therefore making easy to use the produced energy in municipal self consumption or to provide facilities to the citizens. In order to perform such evaluation, a detailed model of the water supply network has been implemented in EPANET parting from a GIS model. The first step of the evaluation has consisted in the optimizing and validation of the model. Initially, the model was reviewed by comparing pressure and flow rate measurements in the main pipes. Then, an extensive experimental campaign was designed. In that campaign valves were switched so that each day a set of District Metered Areas (DMA) have just one metered inlet or at the most a very short number of metered inlets, whereas having a set of pressure measurements within the DMA. The obtained data was used to minimize errors in pressure time series, optimising roughness of the main pipes through Levenberg/Marquardt BFGS algorithm using EPANET ToolKit through Epanet-Octave [2]. Important roughness proposed changes tended to be located surrounding particular points, where errors in the GIS were located (mainly wrong diameter assignement). After patching all the errors the algorithm eased to localise, model errors were mostly below measures uncertainty, and therefore, the model was considered validated. Then, the hydraulic potential at the DMAs inlets has been evaluated by tracking the “instantaneous” minimum pressure and head within each DMA, as well as the flow rate entering the DMA. So that, the maximum head and the range of flow rates is established for the turbine. At the moment, once that all of these potentials have been assessed, a turbine prototype is being designed

    Proposals of a procedure to asses Pollutographs. Application to Murcia's Combined Sewer Overflows (CSOs). Póster

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    Directives 91/271/EEC and 93/481/EEC set norms regarding the management of Combined Sewer Overflows. European Commission monitors the implementation status and implementation programmes. In fact, during the year 2019 all the utilities should be able to quantify the pollution spilled during storm events. And afterwards, plans have to be developed in order to reduce the impact of such events. In this paper, we proposed a method to estimate the transported pollution during events as well as to serve as a tool for developing plans to lessen the corresponding pollution. The procedure is divided into three steps: A. Periodical measurements of all relevant pollutants, e.g. total suspended solids and chemical oxygen demand, in wet and dry weather. Such pollutant “concentrations” are correlated with the turbidity, updating the relation among them [1]. B. Continuous measures of the turbidity. Turbidity is continously register in the sewer areas near overflow spillways. Turbidimeters are a very convenient equipment for this purpose [2]. Actually, it is reliable, its measures are very correlated with the total suspended solid concentration and its maintenance is easy. In this way, combining A. and B. turbidity measures provide us a real-time estimation of the pollutant concentration. on real time. C. Assesment of each catchment hydrograph. Depending on the available data, this step could be based on a design, a measured or a simulated hydrograph. In order to apply this methodology to Murcia’s Combined Sewer System, we have used simulated hydrographs based on real measured rainfall. Murcia’s utility has developed a calibrated SWMM model, and therefore, using the rainfall data, it is possible to estimate hydrographs for all the relevant points of the system. D. Estimation of each catchment pollutograph. Combining the pollutant concentration, estimated in the previous steps, with the hydrographs, we can asses how the mass of pollutants are transported. This information allows us to comply with EU Directives, but it will also be useful to design Murcia’s strategy to minimize environmental impacts

    Numerical Simulations And Laboratory Measurements In Hydraulic Jumps

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    Hydraulic jump is one of the most extended and effective mechanism for hydraulic energy dissipation. Usually, hydraulic jump characteristics have been studied through physical models. Nowadays, computational fluid dynamics (CFD) are an important tool that can help to analyze and to understand complex phenomena that involve high turbulence and air entrainment cases. Free and submerged hydraulic jumps with Froude numbers from 2.9 to 5.5 are studied in a rectangular channel downstream a sluice gate. Velocity measurements with different flow rates are carried out by using Acoustic Doppler Velocimeter (ADV) and Particle Image Velocimeter (PIV) instrumentations. In this paper, laboratory measurements are used to calibrate and to validate open source and commercial CFD programs. Air-water two-phase flows are considered in the simulations. The closure problem is solved by using different turbulence models. Water depths, hydraulic jumps lengths, velocity profiles and energy dissipation rates are compared with laboratory measurements and other referenced results

    Estudio experimental de bloques de impacto trapezoidales

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    [ESP] La misión principal de las estructuras disipadoras de energía en grandes presas es reducir el tamaño y, por tanto, el coste de los cuencos disipadores de energía. Con ellas se consigue un acortamiento de la longitud del resalto hidráulico, limitando, así, la erosión o socavación a pie de presa y su posible vuelco. El objetivo de este trabajo es la realización de un contraste teórico-práctico con otros estudios realizados por diferentes autores sobre estructuras disipadoras de energía. [ENG] The main aim of energy dissipators structures at large dams is to reduce the size, and thus the cost of stilling basins. Such reduction is obtained by shortening of the hydraulic jump length, in this way erosion in the dam base is limited as well as its own spill. The target of this research is the attainment of a theoretical and practical contrast with other research results which have been carried out by different authors about energy dissipative structures.Escuela Técnica Superior de Ingeniería de Telecomunicación (ETSIT), Escuela Técnica Superior de Ingeniería Agronómica (ETSIA), Escuela Técnica Superior de Ingeniería Industrial (ETSII), Escuela Técnica Superior de Arquitectura y Edificación (ETSAE), Escuela Técnica Superior de Ingeniería de Caminos, Canales y Puertos y de Ingeniería de Minas (ETSICCPIM), Facultad de Ciencias de la Empresa (FCCE), Parque Tecnológico de Fuente Álamo (PTFA), Vicerrectorado de Estudiantes y Extensión de la UPCT, Vicerrectorado de Investigación e Innovación de la UPCT, y Vicerrectorado de Internacionalización y Cooperación al Desarrollo de la UPC

    Low-temperature oxidation effects on the morphological and structural properties of hexagonal Zn nanodisks

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    Ambient-atmosphere oxidation in the temperature range of 90-450 C was performed over Zn films composed by well-faceted hexagonal nanodisks, which were deposited by thermal evaporation. Morphological and structural properties of oxidized Zn nanodisks were studied by scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman scattering measurements. It was found that Zn nanodisks keep its original shape only when they are annealed at 90 or 150 C. Smooth oxidation ocurred only on the rectangular faces of Zn nandodisks heated at 150 C. Thermal oxidation at 250 C favored growth of ZnO nanoneedles over the surface of the Zn nanodisks. Hexagonal-shape of Zn nanodisks was transformed completely into a complex morphology composed by different shaped particles, with further increase in oxidation temperature to 450 C

    Exploring structure–activity relationships in photodynamic therapy anticancer agents based on Ir(III)-COUPY conjugates

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    Photodynamic therapy holds great promise as a non-invasive anticancer tool against drug-resistant cancers. However, highly effective, non-toxic, and reliable photosensitizers with operability under hypoxic conditions remain to be developed. Herein, we took the advantageous properties of COUPY fluorophores and cyclometalated Ir(III) complexes to develop novel PDT agents based on Ir(III)-COUPY conjugates with the aim of exploring structure–activity relationships. The structural modifications carried out within the coumarin scaffold had a strong impact on the photophysical properties and cellular uptake of the conjugates. All Ir(III)-COUPY conjugates exhibited high phototoxicity under green light irradiation, which was attributed to the photogeneration of ROS, while remaining non-toxic in the dark. Among them, two hit conjugates showed excellent phototherapeutic indexes in cisplatin-resistant A2780cis cancer cells, both in normoxia and in hypoxia, suggesting that photoactive therapy approaches based on the conjugation of far-red/NIR-emitting COUPY dyes and transition metal complexes could effectively tackle in vitro acquired resistance to cisplatin

    Desarrollo de una instalación experimental minieólica como estrategia de enseñanza-aprendizaje. Póster

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    Se ha desarrollado una plataforma didáctica que consiste en una instalación experimental de energías renovables. La instalación está formada por una planta híbrida eólico-solar. Esta plataforma ha sido diseñada por medio de un proyecto en el que han colaborado la Universidad de Castilla-La Mancha y el Instituto de Educación Secundaria Cencibel de Villarrobledo. La plataforma tiene suficiente flexibilidad como para ser empleada en distintos niveles de formación. De hecho, el objetivo de la misma es mejorar la metodologías de enseñanza actuales tanto en el Máster de Energías Renovables y Eficiencia Energética, como en los Ciclos Formativos de Formación Profesional. Asimismo, la formación de profesionales en este tipo de tecnologías es una apuesta de futuro para la construcción de un sistema energético más sostenible.Campus Mare Nostrum, Universidad Politécnica de Cartagena, Universidad de Murcia, Región de Murci

    Dual-polarized aperture-coupled patch antennas with application to retrodirective and monopulse arrays

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    An isolation technique, which does not require conventional circulators, is proposed for the realization of a simple and low-cost aperture-coupled circularly polarized antenna for application to full-duplex devices. The approach is based on the use of slotlines loops to provide surface current cancellation in specific regions of the antenna structure, leading to improved axial ratio and isolation between the ports in excess of 50 dB. Circular polarization is achieved by introducing a double-box hybrid coupler, which is optimized to obtain good matching and isolation of the quadrature signals. On this basis, both right- and left-hand circularly polarized beams are achieved by interchanging the transmitting and receiving antenna ports, enabling full-duplex operation and reconfigurability. While the antenna structure is designed for 2.45 GHz operation, one can take advantage of the proposed approach to tune the frequency of maximum isolation. Both single-element prototypes as well as a 2 × 2 array are fabricated and measured, showing good agreement with the simulations and validating the proposed isolation approach. The beam steering capabilities as well as the application to a Van Atta retrodirective antenna array and the possibilities of achieving delta and sum patterns for monopulse operation are also reported. The proposed full-duplex antenna can also represent an excellent solution for narrowband wireless power transmission systems

    Multivariate linear regression versus symbolic regression from genetic programming. Application to the spectroscopic characterisation of urban wastewater

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    [EN] Characterising urban wastewater in real time is key to ensure the proper management of water resources and environmental protection. From indirect measurements, such as the molecular spectroscopy which provides information on the physicochemical properties of the water, it is possible to determine the pollutant load of wastewater from mathematical correlation models. The research compares multivariate linear regression models and symbolic regression models based on genetic programming to establish a correlation with the pollutant load of the wastewater. The study has focused on the comparison of models for the characterisation of total nitrogen, total phosphorus and nitrogen in the form of nitrate of 90 urban wastewater samples. It is observed that the symbolic regression based on genetic programming provides an improvement in goodness of fit (R2) of between 72.76% and 146.39% with respect to multivariate linear regression.[ES] Caracterizar en tiempo real las aguas residuales urbanas es clave para poder garantizar una correcta gestión de los recursos hídricos y la protección del medioambiente. A partir de mediciones indirectas, como la espectroscopía molecular que proporciona información sobre las propiedades físico-químicas del agua, es posible determinar la carga contaminante de las aguas residuales empleando modelos matemáticos de correlación. El presente trabajo compara la regresión lineal multivariable y los modelos de regresión simbólica basados en programación genética, para establecer una correlación con la carga contaminante de las aguas residuales. El estudio se ha centrado en la comparativa de modelos para la caracterización de nitrógeno total, fósforo total y nitrógeno en forma de nitrato, considerando 90 muestras de aguas residuales urbanas. Se observa que la regresión simbólica basada en programación genética proporciona una mejora en el ajuste (R2) de entre el 72.76% y 146.39% respecto a la regresión lineal multivariable.El primer autor agradece la financiación recibida de la Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia (España), a través del programa de capacitación para nuevos investigadores en áreas específicas de interés para la industria y alta capacidad de transferencia de los resultados de investigación generados, titulado: “Subprograma Regional de Contratos de Formación de Personal Investigador en Universidades y OPIs” (Mod. B, Ref. 20320/FPI/17)”. El presente trabajo de investigación ha sido financiado mediante el proyecto MONITOCOES: New intelligent monitoring system for microorganisms and emerging contaminants in sewage networks. Referencia: RTC2019-007115-5, otorgado por el Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación, dentro de la convocatoria RETOS COLABORACIÓN 2019. El equipo desarrollado también ha recibido financiación para su industrialización a través del programa “Proof of Concept” de la Fundación Séneca, en el marco del proyecto “ Equipo de MONITORIZACIÓN en Tiempo REAl de Contaminantes en Aguas Residuales (MONITOREA).” (21662/PDC/21.).Carreres-Prieto, D.; García, JT.; Castillo, LG.; Carrillo, JM.; Vigueras-Rodriguez, A. (2022). Regresión lineal multivariable versus regresión simbólica a partir de programación genética. Aplicación a la caracterización espectroscópica de aguas residuales urbanas. Ingeniería del Agua. 26(4):261-277. https://doi.org/10.4995/ia.2022.1807326127726

    Sanitation network sulfide modeling as a tool for asset management. The case of the city of Murcia (Spain)

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    Hydrogen sulfide (H2S) generated in sewer networks induces corrosion which today constitutes the main cause of deterioration of concrete pipes. Information regarding the H2S concentration inside sewer networks, as well as its control and reduction, has become one of the most important concerns in sanitation systems management nowadays. Modeling sulfide dynamics is the key to understanding corrosion processes. A dynamic model (called EMU-SANETSUL) was developed to calculate the H2S concentration in both the water and the gas phases of the main sewers of the city of Murcia (Spain). The model was calibrated with data from field measurements taken from both the gas phase and wastewater. Samples were taken in the network from 2016 to 2019. The model achieved an accuracy index and error index in the ranges of 57% and 15%, respectively. Empirical equations of reaction are used, and calibration parameters are detailed. The code uses an explicit discretization technique, named the Discrete Volume Element Method (DVEM). A map with the annual average concentration of H2S at the gas phase inside each pipe of the simulated network is presented. Values are compared with the mechanical deterioration inventory from closed-circuit television (CCTV) inspections performed by the Municipal Sanitation Company of the city of Murcia (EMUASA). Mechanical deterioration of pipes has diverse causes, including corrosion of pipes by H2S. Sections with high H2S concentrations that match with mechanical wear can be considered susceptible to being prioritized when rehabilitation works are being planned. Therefore, H2S concentration modeling provides valuable information for asset management of the sewer network.This research was funded by the Municipal Sanitation Company of the city of Murcia (EMUASA), grant numbers 4904/17IC-C and 5397/18IC-C from 2016 to 2019 for the Study of preventive and corrective measures to be applied in the sewerage network to minimize corrosion in the concrete pipes of the sewerage network of the city of Murcia by the action of hydrogen sulfide
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