Philippe Dupont - Academia.edu (original) (raw)

Papers by Philippe Dupont

Research paper thumbnail of Kavitation vorhersagen: Numerisches Verfahren verbessert die Konstruktion von Kreiselpumpen

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

Volume 1: Symposia, Parts A, B and C, 2009

In centrifugal pumps, the interaction between the rotating impeller and the stationary diffuser g... more 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 of mechanical vibration levels may negatively affect the operational performance and the life span of mechanical components. This paper presents detailed pressure fluctuation measurements performed in a high speed centrifugal pump stage at full scale at various operating conditions. The impeller and stationary part (diffuser, exit chamber) of the pump stage have been equipped with piezoresistive miniature pressure sensors. The measured data in the impeller have been acquired using a newly developed onboard data acquisition system, designed for rotational speeds up to 6000 rpm. The measurements have been performed synchronously in the rotating and stationary domains. The analysis of pressure fluctuations at the impeller blade trailin...

Research paper thumbnail of Numerical Prediction Of Cavitation In Pumps

ABSTRACT Cavitation is a fundamental issue in pump design. This topic is usually approached throu... more ABSTRACT Cavitation is a fundamental issue in pump design. This topic is usually approached through costly experimental tests. The aim of this work is to apply numerical methodologies to the evaluation of the required Net Positive Suction Head in centrifugal impellers. An industrial pump from WEIR-Gabbioneta SRL has been experimentally analyzed to collect detailed information on the pump behaviour in cavitating conditions. The experimental apparatus has been also analyzed to individuate the pressure levels along the hydraulic circuit. Numerical analyses were performed on a 2D test case representing the NACA 0009 profile using the ANSYS CFX® commercial code. The available cavitation model has been tested and tuned considering different values for the bubble number density, the vapour volume fraction and the bubble diameter. After comparison with the experimental data, the most accurate configuration has been used for the pump simulation. Then, multiphase simulations have been performed using the tuned cavitation model. The computational domain includes several diameters of the hydraulic circuit before the pump and the impeller. The bubble cavitation phenomenon generated by the circuit characteristics as well as the flow pre-swirl at the impeller inlet section are individuated for the lowest flow rate.

Research paper thumbnail of Cavitation erosion power 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June

Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portla... more Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June FED.- pp 3 Reference LMH-CONF-1991-006 Record created on 2005-11-04, modified on 2016-08-08

Research paper thumbnail of Cavitation erosion power

Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portla... more Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June FED.- pp 3 Reference LMH-CONF-1991-006 Record created on 2005-11-04, modified on 2017-11-22

Research paper thumbnail of A Statistical Approach to the Study of Transient Erosive Cavities on a 2D Profile

Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modi... more Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Wake Flow Analysis for a Hydrofoil with and Without Hydroelastic Lock-In

Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04,... more Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04, modified on 2016-08-08

Research paper thumbnail of Cavitation development in a centrifugal pump : numerical and model tests predictions

Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created ... more Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Visualisation du collapse d'une cavité à l'aide d'une caméra vidéo Cranz-Schardin

Note: Using Smart Source Parsing 3-4 juin 3 Reference LMH-CONF-1998-006 Record created on 2005-11... more Note: Using Smart Source Parsing 3-4 juin 3 Reference LMH-CONF-1998-006 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Wake flow analysis for a hydrofoil with and without hydroelastic lock-in

Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04,... more Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04, modified on 2016-08-08

Research paper thumbnail of Etude théorique et expérimentale de la baisse de rendement des turbines Francis par cavitation à bulles

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

Volume 2: Fora, Parts A and B, 2007

Regions of positive slope in the pressure-discharge characteristics can result in a reduction or ... more 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 the admissible operating range. The considered preliminary hydraulic design of an industrial double suction pump of medium specific speed ν = 0.410 (0.205 per impeller side) shows a marked saddle in the energydischarge characteristic associated to a sudden drop of efficiency versus discharge at part load. Unsteady RANS type flow simulations are performed using hexahedral meshes with 2.5 million nodes to model the inlet casing, the shrouded double sided impeller with 2 x 7 blades, the diffuser with 12 blades and the volute. In unsteady solution monitoring, low frequency (below blade passing frequencies) phenomena are noticed. Therefore, simulation times of up to 10 impeller revolutions at each flow rate are requested to achieve statistically steady behavior of the flow judged on global performance numbers and circumferential flow rate distribution. The numerical simulations emphasize a drop in the characteristic, though at a lower flow rate than found on the test rig. It is

Research paper thumbnail of Rotor-Stator Interaction Induced Pressure Fluctuations: CFD and Hydroacoustic Simulations in the Stationary Components of a Multistage Centrifugal Pump

Volume 2: Fora, Parts A and B, 2007

In a centrifugal pump the interaction between the rotating impeller pressure field and the statio... more In a centrifugal pump the interaction between the rotating impeller pressure field and the stationary diffuser pressure field yields pressure fluctuations as the result of a modulation process. These fluctuations may induce hydroacoustic pressure fluctuations in the exit chamber of the pump and could cause unacceptable vibrations. This paper presents a methodology for the prediction of hydroacoustic pressure fluctuations resulting from rotor-stator interaction in a multistage centrifugal pump. The method consists in the one-way coupling of incompressible CFD and hydroacoustic simulations. In a first step the rotorstator pressure fluctuations are calculated using a commercial 3D-RANS CFD-code (CFX 10) for different flow rates. The acoustic simulations are performed in two consecutive steps. Initially a free oscillation analysis using white noise pressure fluctuations is performed, which provides hydroacoustic eigen frequencies and mode shapes of the outlet casing. In a second step th...

Research paper thumbnail of A statistical approach to the study of transient erosive cavities on a 2D profile

Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modi... more Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Partial Sheet Cavities Prediction on a twisted elliptical planform Hydrofoil using a fully 3-D Approach

Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-009 Record created on 20... more Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-009 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Cavitation development in a centrifugal pump: numerical and model tests predictions

Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created ... more Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Prediction of Francis Turbines Efficiency Alteration by travelling Bubble Cavitation

Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-001 Record created on 20... more Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-001 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Cavitation Erosion of the Hydraulic Machines: Generation and Dynamics of Erosive Cavities

Note: Using Smart Source Parsing 20-23 June pp 3 Reference LMH-CONF-1988-003 Record created on 20... more Note: Using Smart Source Parsing 20-23 June pp 3 Reference LMH-CONF-1988-003 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Comparison of flow computation results with experimental flow surveys in a Francis turbine

Note: Using Smart Source Parsing pp 3 Reference LMH-CONF-1994-014 Record created on 2005-11-04, m... more Note: Using Smart Source Parsing pp 3 Reference LMH-CONF-1994-014 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Numerical computation of a leading edge cavity

Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portla... more Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June FED.- pp 3 Reference LMH-CONF-1991-001 Record created on 2005-11-04, modified on 2017-11-22

Research paper thumbnail of Kavitation vorhersagen: Numerisches Verfahren verbessert die Konstruktion von Kreiselpumpen

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

Volume 1: Symposia, Parts A, B and C, 2009

In centrifugal pumps, the interaction between the rotating impeller and the stationary diffuser g... more 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 of mechanical vibration levels may negatively affect the operational performance and the life span of mechanical components. This paper presents detailed pressure fluctuation measurements performed in a high speed centrifugal pump stage at full scale at various operating conditions. The impeller and stationary part (diffuser, exit chamber) of the pump stage have been equipped with piezoresistive miniature pressure sensors. The measured data in the impeller have been acquired using a newly developed onboard data acquisition system, designed for rotational speeds up to 6000 rpm. The measurements have been performed synchronously in the rotating and stationary domains. The analysis of pressure fluctuations at the impeller blade trailin...

Research paper thumbnail of Numerical Prediction Of Cavitation In Pumps

ABSTRACT Cavitation is a fundamental issue in pump design. This topic is usually approached throu... more ABSTRACT Cavitation is a fundamental issue in pump design. This topic is usually approached through costly experimental tests. The aim of this work is to apply numerical methodologies to the evaluation of the required Net Positive Suction Head in centrifugal impellers. An industrial pump from WEIR-Gabbioneta SRL has been experimentally analyzed to collect detailed information on the pump behaviour in cavitating conditions. The experimental apparatus has been also analyzed to individuate the pressure levels along the hydraulic circuit. Numerical analyses were performed on a 2D test case representing the NACA 0009 profile using the ANSYS CFX® commercial code. The available cavitation model has been tested and tuned considering different values for the bubble number density, the vapour volume fraction and the bubble diameter. After comparison with the experimental data, the most accurate configuration has been used for the pump simulation. Then, multiphase simulations have been performed using the tuned cavitation model. The computational domain includes several diameters of the hydraulic circuit before the pump and the impeller. The bubble cavitation phenomenon generated by the circuit characteristics as well as the flow pre-swirl at the impeller inlet section are individuated for the lowest flow rate.

Research paper thumbnail of Cavitation erosion power 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June

Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portla... more Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June FED.- pp 3 Reference LMH-CONF-1991-006 Record created on 2005-11-04, modified on 2016-08-08

Research paper thumbnail of Cavitation erosion power

Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portla... more Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June FED.- pp 3 Reference LMH-CONF-1991-006 Record created on 2005-11-04, modified on 2017-11-22

Research paper thumbnail of A Statistical Approach to the Study of Transient Erosive Cavities on a 2D Profile

Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modi... more Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Wake Flow Analysis for a Hydrofoil with and Without Hydroelastic Lock-In

Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04,... more Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04, modified on 2016-08-08

Research paper thumbnail of Cavitation development in a centrifugal pump : numerical and model tests predictions

Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created ... more Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Visualisation du collapse d'une cavité à l'aide d'une caméra vidéo Cranz-Schardin

Note: Using Smart Source Parsing 3-4 juin 3 Reference LMH-CONF-1998-006 Record created on 2005-11... more Note: Using Smart Source Parsing 3-4 juin 3 Reference LMH-CONF-1998-006 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Wake flow analysis for a hydrofoil with and without hydroelastic lock-in

Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04,... more Note: Using Smart Source Parsing , pp 3 Reference LMH-CONF-1987-003 Record created on 2005-11-04, modified on 2016-08-08

Research paper thumbnail of Etude théorique et expérimentale de la baisse de rendement des turbines Francis par cavitation à bulles

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

Volume 2: Fora, Parts A and B, 2007

Regions of positive slope in the pressure-discharge characteristics can result in a reduction or ... more 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 the admissible operating range. The considered preliminary hydraulic design of an industrial double suction pump of medium specific speed ν = 0.410 (0.205 per impeller side) shows a marked saddle in the energydischarge characteristic associated to a sudden drop of efficiency versus discharge at part load. Unsteady RANS type flow simulations are performed using hexahedral meshes with 2.5 million nodes to model the inlet casing, the shrouded double sided impeller with 2 x 7 blades, the diffuser with 12 blades and the volute. In unsteady solution monitoring, low frequency (below blade passing frequencies) phenomena are noticed. Therefore, simulation times of up to 10 impeller revolutions at each flow rate are requested to achieve statistically steady behavior of the flow judged on global performance numbers and circumferential flow rate distribution. The numerical simulations emphasize a drop in the characteristic, though at a lower flow rate than found on the test rig. It is

Research paper thumbnail of Rotor-Stator Interaction Induced Pressure Fluctuations: CFD and Hydroacoustic Simulations in the Stationary Components of a Multistage Centrifugal Pump

Volume 2: Fora, Parts A and B, 2007

In a centrifugal pump the interaction between the rotating impeller pressure field and the statio... more In a centrifugal pump the interaction between the rotating impeller pressure field and the stationary diffuser pressure field yields pressure fluctuations as the result of a modulation process. These fluctuations may induce hydroacoustic pressure fluctuations in the exit chamber of the pump and could cause unacceptable vibrations. This paper presents a methodology for the prediction of hydroacoustic pressure fluctuations resulting from rotor-stator interaction in a multistage centrifugal pump. The method consists in the one-way coupling of incompressible CFD and hydroacoustic simulations. In a first step the rotorstator pressure fluctuations are calculated using a commercial 3D-RANS CFD-code (CFX 10) for different flow rates. The acoustic simulations are performed in two consecutive steps. Initially a free oscillation analysis using white noise pressure fluctuations is performed, which provides hydroacoustic eigen frequencies and mode shapes of the outlet casing. In a second step th...

Research paper thumbnail of A statistical approach to the study of transient erosive cavities on a 2D profile

Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modi... more Note: Using Smart Source Parsing 3 Reference LMH-CONF-1995-009 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Partial Sheet Cavities Prediction on a twisted elliptical planform Hydrofoil using a fully 3-D Approach

Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-009 Record created on 20... more Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-009 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Cavitation development in a centrifugal pump: numerical and model tests predictions

Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created ... more Note: Using Smart Source Parsing 28-Dec. 3, FED- pp 3 Reference LMH-CONF-1993-001 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Prediction of Francis Turbines Efficiency Alteration by travelling Bubble Cavitation

Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-001 Record created on 20... more Note: Using Smart Source Parsing 7-10 avril pp 3 Reference LMH-CONF-1998-001 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Cavitation Erosion of the Hydraulic Machines: Generation and Dynamics of Erosive Cavities

Note: Using Smart Source Parsing 20-23 June pp 3 Reference LMH-CONF-1988-003 Record created on 20... more Note: Using Smart Source Parsing 20-23 June pp 3 Reference LMH-CONF-1988-003 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Comparison of flow computation results with experimental flow surveys in a Francis turbine

Note: Using Smart Source Parsing pp 3 Reference LMH-CONF-1994-014 Record created on 2005-11-04, m... more Note: Using Smart Source Parsing pp 3 Reference LMH-CONF-1994-014 Record created on 2005-11-04, modified on 2017-05-10

Research paper thumbnail of Numerical computation of a leading edge cavity

Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portla... more Note: Using Smart Source Parsing 91 Symposium, 1st ASME-JSME Fluid Engineering conference, Portland (Oregon), USA, 23-27 June FED.- pp 3 Reference LMH-CONF-1991-001 Record created on 2005-11-04, modified on 2017-11-22