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Hydropower is the world’s most important renewable electricity source. More than 40% of European hydroelectric energy is produced in Alpine countries. High-head storage hydropower plants (HPP) contribute significantly to peak energy production as well as e ...
Hydropower is the world’s most important renewable electricity source. More than 40% of European hydroelectric energy is produced in Alpine countries. High-head storage hydropower plants (HPP) contribute significantly to peak energy production as well as e ...
Modern pump-turbines are subject to frequent switching between the pumping and generating modes with extended operation under off-design conditions. Depending on the specific speed of the pump-turbine, the discharge-speed as well as torque-speed generating ...
Frequent shifts of output and operating mode require a pump turbine with excellent stability. Current researches show that large partial flow conditions in pump mode experience positive-slope phenomena with a large head drop. The pressure fluctuation at th ...
Editorial Office Chinese Journal Mechanical Engineering2012
Draft tube pressure pulsation (DTPP) in Francis turbines is composed of various components originating from different physical phenomena. These components may be separated because they differ by their spatial relationships and by their propagation mechanis ...
International Association For Hydraulic Research2012
The concept studied in this work is a low power ORC-ORC heat pump system (providing about 20 kW heat at the condenser) and that is composed of an ORC power cycle driving a reversed ORC heat pump cycle, both cycles using the same fluid. The centrifugal comp ...
Resonance in hydraulic systems is characterized by pressure fluctuations of high amplitude which can lead to undesirable and dangerous effects, such as noise, vibration and structural failure. For a Francis turbine operating at partial load, the cavitating ...
International Association For Hydraulic Research2012
Progress in materials and manufacturing techniques allows an increase of the mean turbine inlet temperature, resulting in improved efficiency and specific power of the turbine. Because of the combustor characteristics, thermal and aerodynamic nonuniformiti ...
American Institute of Aeronautics and Astronautics2012
Hydraulic pump-turbines are subject to a high periodic excitation due to the Rotor-Stator Interaction, RSI. Basically, the RSI is caused by the impeller blade passage in the wake of the guide vanes in generating mode, or upstream from the guide vanes in pu ...
Pump and turbine operations lead to head losses in the tailrace channel. Pumping discharge may be limited due to potential air entrainment into the pump shaft when the downstream reservoir is at its lowest level and the head losses are high. Regarding turb ...