Conference Presentations by Eduardo Alvarez
Water erosion problems are a major source of problems breaking large fuel pipelines. Currently, t... more Water erosion problems are a major source of problems breaking large fuel pipelines. Currently, the monitoring of these conditions is carried out through on-site inspections. Therefore, it is difficult to anticipate to their possible failure. Due to the economic impact caused by the interruption of fuel supply service, the design of an intelligent monitoring system to prevent the breakage of those pipelines is of high interest. In this line, the present work proposes a design of an automatic system based on the generation of water erosion risk indicators using: field data, captured in remote units, erosion models and algorithms working with historical data.
Los problemas de erosión hídrica son una importante fuente de problemas de rotura de las grandes conducciones de combustible. En la actualidad la supervisión de dichas conducciones se realiza mediante inspecciones presenciales. Por ello, es difícil anticiparse a su posible fallo. Debido al impacto económico provocado por la interrupción del servicio de suministro de combustible, el diseño de un sistema de supervisión inteligente para prevenir la rotura de dichas conducciones es de elevado interés. En dicha línea, este trabajo propone un diseño de sistema automático de generación de indicadores de riesgo de fallo por erosión hídrica que utiliza: datos en campo, captados en unidades remotas, modelos de erosión y algoritmos de trabajo con datos históricos.
Papers by Eduardo Alvarez
Este articulo describe el diseno de una infraestructura de tipo tunel de agua que ha sido constru... more Este articulo describe el diseno de una infraestructura de tipo tunel de agua que ha sido construida y puesta en marcha en la Escuela Politecnica de Mieres (EPM, Universidad de Oviedo). El tunel ha sido concebido como un equipamiento que permite realizar ensayos de distintos prototipos de turbinas hidrocineticas. Incluye un sistema hidraulico calculado para, mediante una recirculacion entre dos tanques, lograr velocidades de agua elevadas en un canal, y un sistema de control (hardware y software) que permite ajustar distintos parametros hidraulicos (velocidad y cota de la lamina de agua) y realizar el control de funcionamiento de la microturbina a ensayar. Mediante la utilizacion del tunel se podran caracterizar distintos disenos de turbina y estrategias de control de las mismas.
Energies, 2021
This article presents the characteristic curves of a vertical-axis hydrokinetic tidal turbine of ... more This article presents the characteristic curves of a vertical-axis hydrokinetic tidal turbine of the Darrieus subtype aimed at meeting the electricity demand of port facilities located at harbors and estuaries with low water-speed conditions. The turbine was tested in the water-current flume of the University of Santiago de Compostela for several flow conditions with different water heights and water speeds. Blockage conditions were tested by examining the results from two groups of tests: with and without an accelerator device that restricts the flow around the rotor. The tip speed ratio and the power coefficient were used to characterize the performance of the turbine for each test. Finally, the results for open-field conditions were obtained by applying empirical expressions, which allowed us to assess the performance of the device in estuaries and harbors with known water-flow regimes.
Clean Technologies and Environmental Policy, 2020
The enormous inroads made by renewable energy in recent years have been the key to the developmen... more The enormous inroads made by renewable energy in recent years have been the key to the development of new technologies designed to obtain energy from a range of resources. Hydrokinetic microturbines used to harness kinetic energy from rivers, tidal and marine currents epitomize such developments. As the reservoir is dispensed with, the water footprint normally associated with conventional hydroelectric generation is minimized. The new prototypes being developed require laboratories with water tunnel infrastructures where they can be accurately reproduced under controlled conditions. However, the construction of a water tunnel demands considerable investment, which prevents many research groups from completing their prototype design work. This paper charts the design of a low-cost hydrodynamic water tunnel at the University of Oviedo, indicating the mechanical and electronic elements as well as the software developments that make up the facility. This construction is a part of a research strategy focused on making the study of new hydrokinetic microturbines designs economically feasible. Moreover, it includes a description of a special software application used to perform the characterization of a hydrokinetic microturbine model in the water tunnel and a demonstration of the scope of the facility in the experimental study of a unit with a Darrieus rotor.
Energies, 2019
Tides can be a vast and predictable source of renewable energy. Due to the solar and lunar influx... more Tides can be a vast and predictable source of renewable energy. Due to the solar and lunar influx on our planet, they move large amounts of water periodically, and this energy can be harnessed using devices designed and positioned adequately, such as current turbines. However, the relation between the energy obtained with actual devices and the economic and environmental cost of their installation limits the practical application of these solutions. In order to optimize the design of this technology and achieve its successful installation and use, a detailed knowledge about the energy potential of tides at the specific location is necessary. This calculation is not easy and requires the use of specialized software tools. Currently, there is no specific software to evaluate the tidal currents energy potential, but there are more than a few codes able to calculate the hydraulic flow in rivers, estuaries and coastal regions. These programs are usually used for the calculation of pollut...
Proceedings, 2018
The present project aims to design the control and monitoring system for a test bench that will h... more The present project aims to design the control and monitoring system for a test bench that will help to calculate the power level that can be extracted from wind vertical axis hydrokinetic microturbines. The workbench includes a hydraulic system calculated to, through a recirculation between two tanks, achieve high fluid speed in the canal, and the monitoring and power electronics systems to adjust different hydraulic parameters and to control the operation of the microturbine under test, providing the necessary measures to obtain the power coefficient versus tip speed ratio (Cp-λ) curves of the microturbine which will help to extract the Maximum Power Point.
Ingeniería del agua, 2021
En el contexto actual de una creciente demanda energética, la energía hidrocinética provocada por... more En el contexto actual de una creciente demanda energética, la energía hidrocinética provocada por la interacción de mareas y caudales de agua en estuarios de los ríos es una de las fuentes con mayor potencial por explotar. En este artículo se presenta el diseño una metodología, que incluye un código que permite automatizar la evaluación de la energía hidrocinética disponible en un estuario, así como el valor de la energía que puede ser aprovechada por turbinas hidrocinéticas de eje vertical a partir de los resultados de simulación obtenidos mediante programas de simulación hidrodinámica. Se ha realizado la integración de dicho código con el software de simulación hidrodinámica IBER, aplicándose la metodología al caso del estuario del río Nalón (Asturias, España).
The International Journal of Advanced Manufacturing Technology, 2013
Development research has been carried out in order to solve a practical industrial problem: to co... more Development research has been carried out in order to solve a practical industrial problem: to counteract axial displacement (axial drift or axial creep) of workpieces during the welding process. Solutions found in the literature generally provide adequate results; however, they are mechanically complex with high purchase and maintenance costs. A mechanically simple and inexpensive solution is proposed in this paper. Axial drift is measured with a lowcost custom-built contact displacement sensor. This sensor can measure axial drift without calibration or setup operations. It is highly robust in order to function correctly in industrial conditions. A pneumatic cylinder moves the idle turning roll along a rail, modifying the longitudinal position of the idle turning roll in order to counteract axial drift. The position of the idle turning roll is controlled by a control algorithm, which consists of a set of rules. Tests were carried out in order to validate the proposed solution, which can be applied to existing turning rolls thereby significantly reducing costs.
IEEE Transactions on Industry Applications, 2011
A laser-stripe system for the automation of welding processes in heavy industries is presented. C... more A laser-stripe system for the automation of welding processes in heavy industries is presented. Conventional methods use human intervention. A new solution using only common usage computer components has been developed, offering at least the same quality of performance at a low price, making laser systems without human intervention attractive for cost sensitive applications in heavy industries. A new system that guarantees satisfactory tracking results even when the welding gap geometry varies strongly or is distorted by noise has been developed.
Smart cities will have a strong impact on the future of renewable energies as terms like sustaina... more Smart cities will have a strong impact on the future of renewable energies as terms like sustainability and energy saving will be more common. In this sense, both of wind and hydrokinetic compact-size turbines, can play an important role in urban communities by providing energy to nearby consumption points in an environmentally suitable way. This work presents the experimental evaluation for a vertical-axis turbine Darrieus type, operating in an open-field wind tunnel and a confined water channel. Power and characteristic curves have been obtained for all test conditions, also the effect of turbine blockage has been evaluated under blockage values ranging from 6.8% to 35%. The peak power coefficient for the confined flow condition reached a value of 0.31 which is 1.5 times higher than the peak one for the experimental open field condition at the same Reynolds number and a blockage of 20%. Finally, two blockage correction equations have been applied to the water channel tests, which ...
Ingeniería del agua, 2015
Las energías marinas disponen de un importante potencial aún por desarrollar. Las elevadas invers... more Las energías marinas disponen de un importante potencial aún por desarrollar. Las elevadas inversiones requeridas, los altos costes de funcionamiento y el elevado impacto ambiental han sido las barreras que han impedido su desarrollo. En este trabajo se realiza una evaluación del potencial energético que es posible aprovechar en la desembocadura del río Nalón utilizando para ello instalaciones de microgeneración. Este tipo de instalaciones pueden ser viables en localizaciones cercanas a la costa al minimizar la inversión necesaria y el coste de operación mantenimiento así como el impacto ambiental. Para ello, se ha trabajado con el programa gratuito de simulación de flujo unidimensional HEC-RAS siendo necesario construir un modelo geométrico de la desembocadura utilizando datos geográficos de libre acceso e información náutica. Los resultados demuestran la existencia de una zona con un potencial energético viable de utilizar desde un punto de vista técnico.
IEEE Transactions on Industry Applications, 2000
A laser-stripe system for the automation of welding processes in heavy industries is presented. C... more A laser-stripe system for the automation of welding processes in heavy industries is presented. Conventional methods use human intervention. A new solution using only common usage computer components has been developed, offering at least the same quality of performance at a low price, making laser systems without human intervention attractive for cost sensitive applications in heavy industries. A new system that guarantees satisfactory tracking results even when the welding gap geometry varies strongly or is distorted by noise has been developed.
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Conference Presentations by Eduardo Alvarez
Los problemas de erosión hídrica son una importante fuente de problemas de rotura de las grandes conducciones de combustible. En la actualidad la supervisión de dichas conducciones se realiza mediante inspecciones presenciales. Por ello, es difícil anticiparse a su posible fallo. Debido al impacto económico provocado por la interrupción del servicio de suministro de combustible, el diseño de un sistema de supervisión inteligente para prevenir la rotura de dichas conducciones es de elevado interés. En dicha línea, este trabajo propone un diseño de sistema automático de generación de indicadores de riesgo de fallo por erosión hídrica que utiliza: datos en campo, captados en unidades remotas, modelos de erosión y algoritmos de trabajo con datos históricos.
Papers by Eduardo Alvarez
Los problemas de erosión hídrica son una importante fuente de problemas de rotura de las grandes conducciones de combustible. En la actualidad la supervisión de dichas conducciones se realiza mediante inspecciones presenciales. Por ello, es difícil anticiparse a su posible fallo. Debido al impacto económico provocado por la interrupción del servicio de suministro de combustible, el diseño de un sistema de supervisión inteligente para prevenir la rotura de dichas conducciones es de elevado interés. En dicha línea, este trabajo propone un diseño de sistema automático de generación de indicadores de riesgo de fallo por erosión hídrica que utiliza: datos en campo, captados en unidades remotas, modelos de erosión y algoritmos de trabajo con datos históricos.