Exploració FLUIDS - Enginyeria de Fluids per data d'edició

Ara es mostren els items 1-20 de 162

    • 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
      Accés obert
      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 ...

    • Shutdown idling performance of the nuclear main coolant pump under station blackout accident: An optimization study 

      Lu, Yonggang; Zhao, Weiqiang; Presas Batlló, Alexandre; Zhu, Rongsheng; Wang, Zhengwei (SAGE publishing, 2022-05-25)
      Article
      Accés restringit per política de l'editorial
      Lead-cooled fast reactor (LFR) is an important reactor type of the Generation IV nuclear energy, and the main coolant pump (MCP) is the only and most critical power equipment in primary circuit of LFR. The shutdown idling ...

    • Failure investigation of a solar tracker due to wind-induced torsional galloping 

      Valentín Ruiz, David; Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Presas Batlló, Alexandre (Elsevier, 2022-05-01)
      Article
      Accés obert
      Solar power installations are increasing every year due to the decarbonization policy established around the world. Photovoltaic (PV) systems and specifically one-axis solar trackers are the most used type of installations ...

    • Prediction of cavitation erosion with different erosion risk indicators 

      Geng, Linlin; Zhang, Dingli; Chen, Jian; Torre Rodríguez, Óscar de la; Escaler Puigoriol, Francesc Xavier (2022-02)
      Article
      Accés obert
      This present work devoted to simulate the unsteady cavitating flow around a hydrofoil and assess its erosion power predicted by different erosion risk indicators. For that, the behavior of unsteady cloud cavity is numerically ...

    • On the use of vibrational hill charts for improved condition monitoring and diagnosis of hydraulic turbines 

      Zhao, Weiqiang; Presas Batlló, Alexandre; Egusquiza Montagut, Mònica; Valentín Ruiz, David; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen (2022-01-22)
      Article
      Accés obert
      To cope with the intermittent power supply of the new renewable energies and demand fluctuations, Francis turbines are required to operate more and more in an extended operating range, far away from the design point. With ...

    • Modelling and adaptive parameter estimation for a piezoelectric cantilever beam 

      Wang, Bin; Costa Castelló, Ramon; Na, Jing; Torre Rodríguez, Óscar de la; Escaler Puigoriol, Francesc Xavier (2022)
      Article
      Accés obert
      This paper proposes a new adaptive estimation approach to online estimate the model parameters of a piezoelectric cantilever beam. The beam behavior is firstly modeled using partial differential equations (PDE) considering ...

    • PZT actuators as on-board instruments to reduce vibrations and strains in submerged structures 

      Sánchez Botello, Xavier; Torre Rodríguez, Óscar de la; Roig Bauzà, Rafel; Costa Castelló, Ramon; Escaler Puigoriol, Francesc Xavier (IOP Publishing, 2022)
      Text en actes de congrés
      Accés obert
      This paper presents the design and evaluation of an active control system to reduce vibrations and strains of submerged structures. For that, a metallic disk mounted in a test rig has been equipped with on-board waterproof ...

    • Dynamic response analysis of a reduced scale Kaplan turbine model operating in propeller mode 

      Escaler Puigoriol, Francesc Xavier; Sánchez Botello, Xavier; Roig Bauzà, Rafel; Torre Rodríguez, Óscar de la; Mulu, Berhanu; Högström, Carl-Maikel (IOP Publishing, 2022)
      Text en actes de congrés
      Accés obert
      In the frame of the AFC4Hydro H2020 research project, an extensive measurement campaign has been carried out on a reduced scale Kaplan turbine model at the Vattenfall Research and Development facility in Älvkarleby, Sweden. ...

    • 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
      Accés obert
      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 ...

    • Understanding the influence of wake cavitation on the dynamic response of hydraulic profiles under lock-in conditions 

      Roig Bauzà, Rafel; Chen, Jian; Torre Rodríguez, Óscar de la; Escaler Puigoriol, Francesc Xavier (2021-09-22)
      Article
      Accés obert
      To accelerate the integration of fluctuating renewable energy technologies in the power systems, it is necessary to increase the flexibility of hydropower by operating turbines at off-design conditions. Unfortunately, this ...

    • Increasing the operating range and energy production in Francis turbines by an early detection of the overload instability 

      Zhao, Weiqiang; Presas Batlló, Alexandre; Egusquiza Montagut, Mònica; Valentín Ruiz, David; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen (2021-08)
      Article
      Accés obert
      With the increasing entrance of wind and solar power for the generation of electricity, more flexibility is demanded to hydropower plants. More flexibility means that hydro turbines have to increase the operating range ...

    • Implant resonance and the mechanostat theory: Applications of therapeutic ultrasound for porous metallic scaffolds 

      Deering, Joseph; Presas Batlló, Alexandre; Yu, Bosco; Valentín Ruiz, David; Heiss, Christian; Bosbach, Wolfram A.; Grandfield, Kathryn (Elsevier, 2021-06-01)
      Article
      Accés obert
      The development of treatment strategies for improving secondary stability at the bone-implant interface is a challenge. Porous implants are one solution for improving long-term implant stability, but the osteoconduction ...

    • On the use of neural networks for dynamic stress prediction in Francis turbines by means of stationary sensors 

      Presas Batlló, Alexandre; Valentín Ruiz, David; Zhao, Weiqiang; Egusquiza Montagut, Mònica; Valero Ferrando, Ma. del Carmen; Egusquiza Estévez, Eduard (Elsevier, 2021-06-01)
      Article
      Accés obert
      Nowadays, one of the major mechanical issues of hydraulic turbines and particularly Francis turbines are the failures produced by fatigue. Due to the massive entrance of new renewable energies such as wind or solar, hydraulic ...

    • Dynamic behaviour of a Francis turbine during voltage regulation in the electrical power system 

      Vagnoni, Elena; Valentín Ruiz, David; Avellan, François (2021-02-01)
      Article
      Accés obert
      Hydroelectric units can be operated in synchronous condenser mode to provide reactive power to the electrical power system (EPS) for voltage regulation. In this operating mode, the hydraulic turbine consumes active power ...

    • Improved damage detection in Pelton turbines using optimized condition indicators and data-driven techniques 

      Zhao, Weiqiang; Egusquiza Montagut, Mònica; Presas Batlló, Alexandre; Valentín Ruiz, David; Egusquiza Estévez, Eduard (2021-01-07)
      Article
      Accés obert
      The health condition of hydraulic turbines is one of the most critical factors for the operation safety and financial benefits of a hydro power plant. After the massive entrance of intermittent renewable energies, hydropower ...

    • On the quantification of local power densities in a new vibration bioreactor 

      Valentín Ruiz, David; Presas Batlló, Alexandre; Roehr, Charline; Mele, Elisa; Bieh, Christoph; Heiss, Christian; Bosbach, Wolfram A. (Public Library of Science (PLOS), 2021-01-01)
      Article
      Accés obert
      We investigate the power densities which are obtainable locally in a vibration bioreactor. These reactor systems are of great relevance for research about oncological or antibacterial therapies. Our focus lies on the local ...

    • Numerical investigation of the effects of hydrofoil vibrations on the unsteady behavior of cavitation 

      Geng, Linlin; Chen, Jian; Torre Rodríguez, Óscar de la; Escaler Puigoriol, Francesc Xavier (Institute of Physics (IOP), 2021)
      Text en actes de congrés
      Accés obert
      In order to better understand the fluid-structure interaction (FSI) in hydraulic machines, this study aims to numerically investigate the flow around an oscillating hydrofoil with special attention on the effect of ...

    • Assessment of turbulence models for the prediction of Bénard- Von Kármán vortex shedding behind a truncated hydrofoil in cavitation conditions 

      Chen, Jian; Geng, Linlin; Torre Rodríguez, Óscar de la; Escaler Puigoriol, Francesc Xavier (Institute of Physics (IOP), 2021)
      Text en actes de congrés
      Accés obert
      The transient cavitating flow in the wake of a hydrofoil at zero incidence angle has been simulated using a homogeneous mixture cavitation mass transfer model combined with both Reynolds Average Navier-Stokes (RANS) and ...

    • Numerical assessment of parameters influencing the modal response of a Kaplan turbine model 

      Roig Bauzà, Rafel; Torre Rodríguez, Óscar de la; Jou Santacreu, Esteban; Escaler Puigoriol, Francesc Xavier (Institute of Physics (IOP), 2021)
      Text en actes de congrés
      Accés obert
      The present study intends to investigate numerically the impact of: i) the fluid added mass, ii) the turbine rotational speed and iii) the variation of the runner blade bearing stiffness due to the turbine water head on ...

    • Strain prediction in Francis runners by means of stationary sensors 

      Presas Batlló, Alexandre; Valentín Ruiz, David; Zhao, Weiqiang; Valero Ferrando, Ma. del Carmen; Egusquiza Montagut, Mònica; Egusquiza Estévez, Eduard (2021)
      Text en actes de congrés
      Accés obert
      The assessment of the remaining useful life due to fatigue in Francis turbine runners implies complex measurements with strain gauges that have to be installed in a submerged and rotating structure, which is excited with ...