FRBB - GESE - ARTICULOS

Permanent URI for this collectionhttp://48.217.138.120/handle/20.500.12272/635

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    Aerodynamic performance of straight-bladed vertical axis wind turbines : a practical open source implementation
    (2017-10-18) Vitale, Alejandro; Genchi, Sibila; Rossi, Andrea; Guillermo, Eduardo; di Prátula, Horacio
    This study presents a practical open source implementation that uses double-multiple streamtube model for the aerodynamic performance prediction of straight-bladed vertical axis wind turbines, particularly, the power coefficient (Cp) and tip speed ratio (λ) relationship. To improve the analytical capability of the proposed implementation, important aspects of performance such as dynamics stall and, fixed/variable pitch blade were added. In addition, a fast convergence method for finding the axial induction factor was adopted, giving simplicity to the implementation. Simulated Cp(λ) curves were compared with the experimental data (wind tunnel and field) reported in the literature. The mean absolute error of the simulated Cp(λ) curves, in terms of efficiency, was 0.06, with a mean maximum of 0.078 and a mean minimum of 0.047. The good agreement in combination with the low computing time, suggests that the proposed implementation provides a useful tool for predicting aerodynamic properties of the straight-bladed vertical axis wind turbines and, therefore, for its design. The implementation can be carried out successfully by using GNU-Octave
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    Electrical and magnetic response of a phosphate glass – NiFe2O4 composite : a novel magnetic sensor design
    (2019-01-29) di Prátula, Pablo Emmanuel; Pistonesi, Carlos Alberto; Antón, Marcelo Alejandro; di Prátula, Horacio Raúl; Guillermo, Eduardo Daniel; Frechero, Marisa Alejandra
    NiFe2O4 spinel – phosphate (Bi-Ba-Li) glass composite was synthesized by solid-state reaction. New crystalline magnetic phases was developed inside the glassy matrix through a controlled heat treatment. New NF-LBPB4 magnetic nanocomposite material was study. Complex impedance analysis has shown that mobile ions inside the matrix induce the development of complementary crystalline phases resulting in a composite material with excellent magnetic response. An innovative homemade device was designed to test the nanocomposite magnetic response.
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    Turbinas eólicas. Optimización en el pre-diagnóstico de fallas en el generador. Otros titulos: Wind Turbine. Optimization of Failures Pre-Diagnosis in the Power Generator
    (2012) di Prátula, Horacio Raúl; Guillermo, Eduardo Daniel; Rossi, Andrea Paula; Bocero, Rodolfo Luis;
    Se propone un método no invasivo y de bajo costo para el pre-diagnóstico de fallas en a máquina eléctrica de grandes aerogeneradores. Esto con el objeto de minimizar el riesgo de falla y la remoción de la máquina con uso de equipo pesado (grúas) para reparaciones. Dado que es usual recurrir a más de un método para detectar fallas incipientes, la predicción requiere corroboración para mayor seguridad. En la industria, esta práctica es normal (medir vibraciones y espectro de corriente, por ejemplo), pero optimizar el mantenimiento predictivo de una máquina eléctrica fijada en una turbina eólica requiere de la menor cantidad posible de dispositivos y de la factibilidad de utilizar monitoreo a distancia con métodos no invasivos. El método propuesto reúne estas condiciones y los ensayos preliminares con sensores de bajo costo muestran buenos resultados para su aplicación experimental. A non-invasive low cost method for pre-diagnosis faults in electrical machines of large wind turbines is proposed. The objective is to minimize fault risks and the removal of the machine with heavy equipment (such as cranes) for maintenance. Since it is normal to use more than one method to detect incipient faults, prediction requires corroboration for higher security (such as vibration measurement and current spectrum analyses). This practice is usual in industries, but optimum predictive maintenance of electric machines in a wind turbine requires the use of the fewest possible devices and a distance non-invasive monitoring method. The proposed method has all this characteristics and preliminary essays with low cost sensors show good results for experimental applications.