Ara es mostren els items 1-12 de 432

    • Numerical theory and method on the modal behavior of a pump-turbine rotor system considering gyro-effect and added mass effect 

      Cao, Jingwei; Luo, Yongyao; Liu, Xin; Presas Batlló, Alexandre; Deng, Liwei; Zhao, Weiqiang; Xia, Ming; Wang, Zhengwei (Elsevier, 2024-04-30)
      Article
      Accés restringit per política de l'editorial
      The pump-turbine unit is the core equipment of pumped storage power station, and the rotor system is the key component of the pump-turbine unit. In this paper, the numerical method considering the gyro-effect and added ...
    • Ocean quadcopters: persistent and autonomous aerial surveillance of large maritime areas by quadcopters self-powered by ocean waves 

      Arias Montenegro, Francisco Javier; Heras Jiménez, Salvador Augusto de las (Springer, 2024-03-15)
      Article
      Accés restringit per política de l'editorial
      In this work consideration is given to the possibility for persistent aerial surveillance of oceans by means of quadcopters capable of taking off and landing on the sea and charging their batteries by the waves from the ...
    • Magnetically induced gluing bifurcations of three-tori in spherical Couette flows 

      García González, Fernando (American Institute of Physics (AIP), 2023-11-27)
      Article
      Accés obert
      The global dynamics of three-tori associated with homoclinic/heteroclinic global (infinite period) bifurcations are investigated for the magnetized spherical Couette problem, a paradigmatic model in geo- and astrophysical ...
    • Analysis of a novel fluidic oscillator under several dimensional modifications 

      Karimzadegan, Kavoos; Mirzaei, Masoud; Bergadà Granyó, Josep Maria (Multidisciplinary Digital Publishing Institute, 2024-02-20)
      Article
      Accés obert
      To activate the boundary layer in Active Flow Control (AFC) applications, the use of pulsating flow has notable energy advantages over constant blowing/suction jet injections. For a given AFC application, five parameters, ...
    • Flow regime analysis of high-pressure transcritical fluids in microducts 

      Bandarrinha Monteiro, Carlos Alexandre; Jofre Cruanyes, Lluís (2024-06)
      Article
      Accés obert
      Microduct flows are known for their inherent laminar regimes resulting from the characteristic small dimensions and low velocities. In this regard, direct numerical simulations are employed to investigate an innovative ...
    • A hybrid control-oriented PEMFC model based on echo state networks and gaussian radial basis functions 

      Aguilar Plazaola, José Agustín; Chanal, Damien; Chamagne, Didier; Yousfi-Steiner, Nadia; Péra, Marie-Cécile; Husar, Attila Peter; Andrade-Cetto, Juan (2024-01-01)
      Article
      Accés obert
      The goal of increasing efficiency and durability of fuel cells can be achieved through optimal control of their operating conditions. In order to implement such controllers, accurate and computationally efficient fuel cell ...
    • State machine-based architecture to control system processes in a hybrid fuel cell electric vehicle 

      Molavi, Ali; Husar, Attila Peter; Hjortberg, Hampus; Nilsson, Niclas; Kogler, Markus; Monreal, Juan Sanchez; Eldigair, Yousif; Serra, Maria (Elsevier, 2023-07-20)
      Article
      Accés obert
      This paper presents the development and implementation of a system supervisory controller in a hydrogen-based fuel cell electric vehicle. The controller's primary function is to ensure the safe control of the fuel cell ...
    • Experimental control of a methanol catalytic membrane reformer 

      Cifuentes López, Alejandro; Serra, Maria; Torres Cámara, Ricardo; Llorca Piqué, Jordi (Multidisciplinary Digital Publishing Institute (MDPI), 2023-11-06)
      Article
      Accés obert
      A simple proportional integral (PI) controller with scheduled gain has been developed and implemented in a catalytic membrane reactor (CMR) to obtain pure hydrogen from a methanol steam reforming process. The controller ...
    • Artificial compressibility method for high-pressure transcritical fluids at low Mach numbers 

      Abdellatif, Ahmed Mohammed Abdelfattah; Ventosa Molina, Jordi; Grau Barceló, Joan; Torres Cámara, Ricardo; Jofre Cruanyes, Lluís (Elsevier, 2024-02-15)
      Article
      Accés obert
      Supercritical fluids possess unique properties that makes them relevant in various scientific and engineering applications. However, the experimental investigation of these fluids is challenging due to the high pressures ...
    • On the vaneless space vortex structures in a Kaplan turbine model operating at speed no load 

      Roig Bauzà, Rafel; Sánchez Botello, Xavier; Mulu, Berhanu; Högström, Carl-Maikel; Escaler Puigoriol, Francesc Xavier (Multidisciplinary Digital Publishing Institute, 2023-12-15)
      Article
      Accés obert
      The growing installation of intermittent renewable energy sources is forcing hydraulic turbines to work more frequently at speed no load when dangerous vaneless space vortex structures and stochastic flow phenomena can ...
    • Cost vs accuracy: DNS of turbulent flow over a sphere using structured immersed-boundary, unstructured finite-volume, and spectral-element methods 

      Capuano, Francesco; Beratlis, Nikolaos; Zhang, Fengrui; Peet, Yulia; Squires, Kyle; Balaras, Elias (Elsevier, 2023-11-01)
      Article
      Accés restringit per política de l'editorial
      We report a comparative study of three numerical solvers for the direct numerical simulation of the flow over a sphere at Re = 3700. A high-order spectral-element code (Nek5000), a general purpose, unstructured finite-volume ...
    • Prediction of the characteristic pressure pulsations in a reversible pump-turbine 

      Fontanals García, Alfred; Guardo Zabaleta, Alfredo de Jesús; Coussirat Núñez, Miguel Gustavo; Moll, Flavio; Egusquiza Estévez, Eduard; Martínez, Germán (2023-11)
      Article
      Accés obert
      Reversible Pump- Turbine turbomachines are frequently used in peaking load hydroelectrical power plants. These plants contribute to satisfy the energy demand during peak load periods. Its dynamic behaviour is influenced ...