Articles de revista: Enviaments recents
Ara es mostren els items 13-24 de 78
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Understanding the influence of wake cavitation on the dynamic response of hydraulic profiles under lock-in conditions
(2021-09-22)
Article
Accés obertTo 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
(2021-08)
Article
Accés obertWith 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 ... -
Dynamic behaviour of a Francis turbine during voltage regulation in the electrical power system
(2021-02-01)
Article
Accés obertHydroelectric 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 ... -
Dynamic response of Pelton runners: Numerical and experimental analysis in prototypes
(Elsevier, 2020-09-01)
Article
Accés obertWorldwide electricity generation is featured by the growth of intermittent renewable energies. In this context, hydropower plays a fundamental role because it provides flexibility to the power grid and ensures its stability. ... -
Operating conditions leading to crack propagation in turbine blades of tidal barrages. Influence of head and operating mode
(Elsevier, 2020-01)
Article
Accés obertTidal energy systems and specifically tidal barrages are renewable energy systems, that use the potential energy of tides to produce electricity. Actually, there are few tidal power stations operating, although recent ... -
Numerical simulation of cavitation erosion aggressiveness induced by unsteady cloud cavitation
(Multidisciplinary Digital Publishing Institute, 2020-08-01)
Article
Accés obertA numerical investigation of the erosion aggressiveness of leading edge unsteady cloud cavitation based on the energy balance approach has been carried out to ascertain the main damaging mechanisms and the influence of the ... -
Response of Saos-2 osteoblast-like cells to kilohertz-resonance excitation in porous metallic scaffolds
(Elsevier, 2020-06-01)
Article
Accés obertPost-operative therapy for joint replacement is often performed to optimize bone volume and bone-implant contact. Methods, such as pulsed therapeutic ultrasound, have been shown to be a valuable addition to regular ... -
Transposition of the mechanical behavior from model to prototype of Francis turbines
(Elsevier, 2020-06-01)
Article
Accés obertHydropower is nowadays essential for balancing the electrical grid providing flexibility and fast response. The role of hydraulic turbines has changed from working at their Best Efficiency Point (BEP) to work in the whole ... -
Synchronous condenser operation in Francis turbines: Effects in the runner stress and machine vibration
(Elsevier, 2020-02-01)
Article
Accés obertReactive power shortage is one of the current issues that endanger the stability of the power grid systems. Some massive blackouts have been experienced in the past years due to the unbalance of reactive power. One of the ... -
Numerical analysis of the influence of design parameters on the efficiency of an OWC axial impulse turbine for wave energy conversion
(2019-03-12)
Article
Accés obertOscillating water column (OWC) axial impulse turbines permit the conversion of wave energy into electrical power. Unlike other hydropower units with a mature and well established technology, such turbines have been recently ... -
Experimental measurements of the natural frequencies and mode shapes of rotating disk-blades-disk assemblies from the stationary frame
(Multidisciplinary Digital Publishing Institute, 2019-09-14)
Article
Accés obertDetermining the natural frequencies and mode shapes of rotating turbomachinery components from both rotating and stationary reference frames is of paramount importance to avoid resonance problems that could affect the ... -
Cavitation effects on the structural resonance of hydraulic turbines: Failure analysis in a real francis turbine runner
(2018-09-03)
Article
Accés obertWhen discussing potential resonances in hydraulic turbine runners, cavitation effects are usually neglected. Nevertheless, recent studies have experimentally proved, that large cavitation volumes in the proximity of flexible ...