Now showing items 1-20 of 61

    • A novel condition monitoring methodology based on neural network of pump-turbines with extended operating range 

      Zhao, Weiqiang; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Valentín Ruiz, David; Presas Batlló, Alexandre (2019)
      Conference report
      Open Access
      Due to the entrance of new renewable energies, water-storage energy has to be regulated more frequently to keep the stability of power grid. Consequently, pump-turbines have to work under offdesign conditions more than ...
    • Accurate determination of the frequency response function of submerged and confined structures by using PZT-patches 

      Presas Batlló, Alexandre; Valentín Ruiz, David; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Bossio, Matias (2017-03-22)
      Article
      Open Access
      To accurately determine the dynamic response of a structure is of relevant interest in many engineering applications. Particularly, it is of paramount importance to determine the Frequency Response Function (FRF) for ...
    • Advanced condition monitoring of Pelton turbines 

      Egusquiza Montagut, Mònica; Valero Ferrando, Ma. del Carmen; Presas Batlló, Alexandre; Valentín Ruiz, David; Bossio, Matias; Egusquiza Estévez, Eduard (2017)
      Conference report
      Restricted access - publisher's policy
      The ability of hydropower to adapt the electricity generation to the demand is necessary to integrate wind and solar energy to the grid. Nowadays hydropower turbines are required to work under harsher operating conditions ...
    • Advanced condition monitoring of Pelton turbines 

      Egusquiza Montagut, Mònica; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Presas Batlló, Alexandre; Valentín Ruiz, David; Bossio, Matias (2018-04)
      Article
      Open Access
      The ability of hydropower to adapt the electricity generation to the demand is necessary to integrate wind and solar energy into the electrical grid. Nowadays, hydropower turbines are required to work under harsher operating ...
    • Analysis if the dynamic response of pump-turbine runners- Part I: Experiment 

      Presas Batlló, Alexandre; Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard; Huang, Xingxing; Farhat, Mohamed; Avellan, François (2012)
      Conference report
      Restricted access - publisher's policy
      When in operation, pump-turbine runners have to withstand large pressure pulsations generated by the rotor-stator interaction. The analysis of the dynamic behavior of these structures is necessary to avoid damage. For this ...
    • Analysis of the dynamic response of pump-turbine impellers. Influence of the rotor 

      Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Presas Batlló, Alexandre; Huang, Xingxing; Guardo Zabaleta, Alfredo de Jesús; Seidel, Ulrich (2016-02-01)
      Article
      Open Access
      This paper deals with the dynamic response of pump-turbine impellers. A pump-turbine impeller is a complex structure attached to a rotor and rotating inside a casing full of water with very small clearances between the ...
    • Analysis of the dynamic response of pump-turbine runners. Part I: Experiment 

      Presas Batlló, Alexandre; Valero Ferrando, Ma. del Carmen; Huang, Xingxing; Egusquiza Estévez, Eduard; Farhat, Mohamed; Avellan, François (IOPScience, 2012)
      Conference lecture
      Restricted access - publisher's policy
      When in operation, pump-turbine runners have to withstand large pressure pulsations generated by the rotor-stator interaction. The analysis of the dynamic behavior of these structures is necessary to avoid damage. For this ...
    • Analysis of the mode shapes of Kaplan runners 

      Moraga González, Greco Alonso; Egusquiza Montagut, Mònica; Valentín Ruiz, David; Valero Ferrando, Ma. del Carmen; Presas Batlló, Alexandre (Multidisciplinary Digital Publishing Institute, 2022-07-02)
      Article
      Open Access
      To prevent lifetime shortening and premature failure in turbine runners, it is of paramount importance to analyse and understand its dynamic response and determine the factors that affect it. In this paper, the dynamic ...
    • Assessment of the economic and environmental impact of double glazed façade ventilation systems in Mediterranean climates 

      Valentín Ruiz, David; Guardo Zabaleta, Alfredo de Jesús; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Alavedra, Pere (2013-09-30)
      Article
      Open Access
      Free convection is the most often used method in order to reduce solar load gains on a building with double glazed façades (DGFs). However, depending on the climate factors, the thermal performance of a DGF may not be ...
    • Behavior of Francis turbines at part load. Field assessment in prototype: Effects on power swing. 

      Valentín Ruiz, David; Presas Batlló, Alexandre; Egusquiza Montagut, Mònica; Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard (Institute of Physics (IOP), 2019)
      Conference report
      Open Access
      Francis turbines are increasingly demanded to work at part load in order to satisfy the electricity generation demand and to compensate the non-constant generation of other renewable sources such as wind or solar. At part ...
    • Behavior of Francis turbines at part load. Field assessment in prototype: Effects on the hydraulic system. 

      Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Valentín Ruiz, David; Presas Batlló, Alexandre; Egusquiza Estévez, Eduard (Institute of Physics (IOP), 2019)
      Conference report
      Open Access
      At present, hydropower plants play an important role because of their flexibility in the generation of electricity. Today, the required operating range of turbine units is expected to extend to deep part load. At part load ...
    • CFD study of the effects of ingested bodies on the RSI of hydraulic turbines 

      Guardo Zabaleta, Alfredo de Jesús; Fontanals García, Alfred; Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard (2018)
      Conference report
      Open Access
      The ingestion of large bodies in hydraulic turbines can produce blockage in the runner and/or the distributor, modifying the amplitude and uniformity of pressure pulsations and generating large ...
    • Characterization of the effects of ingested bodies on the rotor–stator interaction of hydraulic turbines 

      Guardo Zabaleta, Alfredo de Jesús; Fontanals García, Alfred; Egusquiza Montagut, Mònica; Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard (2021-10-14)
      Article
      Open Access
      Runner and distributor blockages in hydraulic turbines occur due to the ingestion of external bodies such as rocks or logs. These obstructions can change the amplitude and uniformity of the pressure pulsations in the ...
    • Computational fluid dynamics modeling of impinging gas-jet systems: II. Application to an industrial cooling system device 

      Coussirat Núñez, Miguel Gustavo; van Beeck, J; Mestres Ridge, Marc; Egusquiza Estévez, Eduard; Buchlin, J-M; Valero Ferrando, Ma. del Carmen (2005-07-15)
      Article
      Restricted access - publisher's policy
      A numerical analysis of the flow behavior in industrial cooling systems based on arrays of impinging jets has been performed, using several eddy viscosity models to determine their modeling capabilities. For the cooling ...
    • Condition monitoring of a prototype turbine. Description of the system and main results 

      Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard; Presas Batlló, Alexandre; Valentín Ruiz, David; Egusquiza Montagut, Mònica; Bossio, Matias (Institute of Physics (IOP), 2017)
      Conference report
      Open Access
      The fast change in new renewable energy is affecting directly the required operating range of hydropower plants. According to the present demand of electricity, it is necessary to generate different levels of power. Because ...
    • Condition monitoring of pump-turbines 

      Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard (2014)
      Conference report
      Restricted access - publisher's policy
      At present, new renewables like wind, solar and marine energy are having a strong development. The generation of energy by renewables has the disadvantage that it depends on atmospheric conditions. It means that they ...
    • Condition monitoring of pump-turbines. New challenges 

      Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen; Valentín Ruiz, David; Presas Batlló, Alexandre; Rodriguez Godoy, Cristian (2015-05)
      Article
      Open Access
      At present, pumped storage is the only system to store huge amounts of energy. The surplus of energy in the electrical grid is used for pumping water from a lower to a higher reservoir (pump operation). At peak hours or ...
    • Detection and analysis of part load and full load instabilities in a real Francis turbine prototype 

      Presas Batlló, Alexandre; Valentín Ruiz, David; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen (Institute of Physics (IOP), 2017)
      Conference report
      Open Access
      Francis turbines operate in many cases out of its best effici ency point, in order to regulate their output power according to the instantaneous ener gy demand of the grid. Therefore, it is of paramount importance to analyse ...
    • Detection of erosive cavitation on hydraulic turbines through demodulation analysis 

      Presas Batlló, Alexandre; Luo, Yongyao; Valentín Ruiz, David; Egusquiza Montagut, Mònica; Wang, Zhengwei; Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard (Institute of Physics (IOP), 2018)
      Conference report
      Open Access
      Erosive cavitation in hydraulic turbines affects severely the runner structure, increasing maintenance costs and reducing the remaining useful life of the component. Actual vibro-acoustic techniques used to detect this ...
    • Detection of hydraulic phenomena in francis turbines with different sensors 

      Valentín Ruiz, David; Presas Batlló, Alexandre; Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Egusquiza Estévez, Eduard (Multidisciplinary Digital Publishing Institute (MDPI), 2019-09-19)
      Article
      Open Access
      Nowadays, hydropower is demanded to provide flexibility and fast response into the electrical grid in order to compensate the non-constant electricity generation of other renewable sources. Hydraulic turbines are therefore ...