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Concept

Impeller

Publications associées (29)

Experimental Evidence of Rotating Stall in a Pump-Turbine at Off-Design Conditions in Generating Mode

François Avellan, Mohamed Farhat, Vlad Hasmatuchi, Steven Roth

An experimental investigation of the rotating stall in reduced scale model of a low specific speed radial pump-turbine at runaway and turbine brake conditions in generating mode is achieved. Measurements of wall pressure in the stator are performed along w ...

American Society of Mechanical Engineers2011

Effect of Stators on the Performance and the Thermal Capabilities of Small Axial Cooling Fans

Peter Ott, Alexandros Terzis

This investigation examines experimentally the effect of stators on the performance curves and the heat transfer capabilities of small axial cooling fans. The experimental data indicated that the results are highly affected by the flow conditions at the fa ...

2011

Modal behavior of a reduced scale pump-turbine impeller. Part 1: Experiments

François Avellan, Mohamed Farhat

An experimental investigation has been carried out to quantify the effects of surrounding fluid on the modal behavior of a reduced scale pump-turbine impeller. The modal properties of the fluid-structure system have been obtained by Experimental Modal Anal ...

International Association For Hydraulic Research2010

Hydrodynamics of High Specific Power Pumps for Off-Design Operating Conditions

Part load operation of high energy centrifugal pumps is associated with increased vibration levels which may adversely affect the machines operational safety. The main sources of vibrations in centrifugal pumps are of hydrodynamic nature. The interaction b ...

EPFL2010

Part load flow in radial centrifugal pumps

Centrifugal pumps are required to sustain a stable operation of the system they support under all operating conditions. Minor modifications of the surfaces defining the pump's water passage can influence the tendency to unstable system operation significan ...

EPFL2009

Experimental Investigation of Flow Instabilities and Rotating Stall in a High-Energy Centrifugal Pump Stage

François Avellan, Maher Kayal, Mohamed Farhat, Philippe Dupont, Laurent Fabre

In centrifugal pumps, the interaction between the rotating impeller and the stationary diffuser generates specific pressure fluctuation patterns. When the pump is operated at off design conditions, these pressure fluctuations increase. The resulting rise o ...

ASME2009

Experimental investigation of a direct driven radial compressor for domestic heat pumps

Daniel Favrat, Jürg Alexander Schiffmann

The presence of oil in domestic heat pumps is an obstacle toward higher efﬁciency, particularly for enhanced surface evaporators and for advanced concepts based on two- stage cycles. Very compact direct driven radial compressors supported on oil-free beari ...

2009

Low power ORC-ORC systems for heat pump applications

Daniel Favrat, Jonathan Demierre

This paper presents a study of a residential (about 20kW) ORC-ORC (Organic Rankine Cycle) thermally driven heat pump. The system works with three different temperature levels similar to absorption heat pumps. The proposed concept is a hermetic system using ...

2008

Unsteady Numerical Simulations of the Flow Related to the Unstable Energy-Discharge Characteristic of a Medium Specific Speed Double Suction Pump

François Avellan, Philippe Dupont

Regions of positive slope in the pressure-discharge characteristics can result in a reduction or even lack of damping of system instabilities. They are therefore one of the major concerns in design and operation of centrifugal pumps as they are limiting th ...

2007