2015
Yang, Jun; Pavesi, Giorgio; Yuan, Shouqi; Cavazzini, Giovanna; Ardizzon, Guido
Experimental Characterization of a Pump–Turbine in Pump Mode at Hump Instability Region Journal Article
In: Journal of Fluids Engineering, vol. 137, iss. 5, pp. 051109, 2015, ISSN: 0098-2202, (<b>From Duplicate 2 (<i>Experimental Characterization of a Pump–Turbine in Pump Mode at Hump Instability Region</i> - Yang, Jun; Pavesi, Giorgio; Yuan, Shouqi; ...; Cavazzini, Giovanna; Ardizzon, Guido)<br/></b><br/><b>From Duplicate 8 (<i>Experimental characterization of a pump–turbine in pump mode at hump instability region</i> - Yang, J; Pavesi, G; Yuan, S; ...)<br/></b><br/>Query date: 2017-05-06).
Abstract | Links | BibTeX | Tags: Flow Visualization, high-speed, High-speed flow visualization, Hump-instability, hump-instability region, Pressure measurement, Pump, Pump as Turbine, Pump as Turbine, Rotating Stall, Turbine
@article{pop00008,
title = {Experimental Characterization of a Pump–Turbine in Pump Mode at Hump Instability Region},
author = {Jun Yang and Giorgio Pavesi and Shouqi Yuan and Giovanna Cavazzini and Guido Ardizzon},
url = {http://fluidsengineering.asmedigitalcollection.asme.org/article.aspx?doi=10.1115/1.4029572},
doi = {10.1115/1.4029572},
issn = {0098-2202},
year = {2015},
date = {2015-01-01},
urldate = {2015-01-01},
journal = {Journal of Fluids Engineering},
volume = {137},
issue = {5},
pages = {051109},
publisher = {… .asmedigitalcollection.asme.org},
abstract = {The unsteady phenomena of a low specific speed pump-turbine operating in pump mode were characterized by dynamic pressure measurements and high-speed flow visualization of injected air bubbles. Analyses were carried out on the pressure signals both in frequency and time-frequency domains and by bispectral protocol. The results obtained by high-speed camera were used to reveal the flow pattern in the diffuser and return vanes channels The unsteady structure identified in the return vane channel appeared both at full and part load condition. Furthermore, a rotating stall structure was found and characterized in the diffuser when the pump operated at part load. The characteristics of these two unsteady structures are described in the paper.},
note = {<b>From Duplicate 2 (<i>Experimental Characterization of a Pump–Turbine in Pump Mode at Hump Instability Region</i> - Yang, Jun; Pavesi, Giorgio; Yuan, Shouqi; ...; Cavazzini, Giovanna; Ardizzon, Guido)<br/></b><br/><b>From Duplicate 8 (<i>Experimental characterization of a pump–turbine in pump mode at hump instability region</i> - Yang, J; Pavesi, G; Yuan, S; ...)<br/></b><br/>Query date: 2017-05-06},
keywords = {Flow Visualization, high-speed, High-speed flow visualization, Hump-instability, hump-instability region, Pressure measurement, Pump, Pump as Turbine, Pump as Turbine, Rotating Stall, Turbine},
pubstate = {published},
tppubtype = {article}
}
The unsteady phenomena of a low specific speed pump-turbine operating in pump mode were characterized by dynamic pressure measurements and high-speed flow visualization of injected air bubbles. Analyses were carried out on the pressure signals both in frequency and time-frequency domains and by bispectral protocol. The results obtained by high-speed camera were used to reveal the flow pattern in the diffuser and return vanes channels The unsteady structure identified in the return vane channel appeared both at full and part load condition. Furthermore, a rotating stall structure was found and characterized in the diffuser when the pump operated at part load. The characteristics of these two unsteady structures are described in the paper.
1999
Guido Ardizzon, Giorgio Pavesi
Analisi Sperimentale della Caratteristica Interna di una Turbomacchina ai Carichi Parziali Proceedings Article
In: MIS - MAC VI Metodi di Sperimentazione nelle Macchine, pp. 63-74, SGE - Padova, 1999.
Abstract | BibTeX | Tags: Losses, part load, Pump, Pump as Turbine, Turbine
@inproceedings{ArdizzonGPavesiG1999,
title = {Analisi Sperimentale della Caratteristica Interna di una Turbomacchina ai Carichi Parziali},
author = {Guido Ardizzon, Giorgio Pavesi},
year = {1999},
date = {1999-01-01},
urldate = {1999-01-01},
booktitle = {MIS - MAC VI Metodi di Sperimentazione nelle Macchine},
pages = {63-74},
publisher = {SGE - Padova},
abstract = {Direct and reverse operation of three radial flow turbomachines at part load conditions are investigated in order to evaluate the energy exchange between runner and fluid. Recirculation phenomena that occur at low flowrates interact with the blade passages with a net exchange momentum which has to be supplied by the impeller in pump mode, while reducing the one transmitted to the rotor by the fluid in turbine mode. Partial flow characteristic curves are also influenced in both operation modes. In order to highlight the role played by backward flows on the performances, the runnerfluid energy transfer has been evaluated from both velocity and power measurements. In particular, leakage and windage losses have been segregated and measured. The experimental results show that when recirculation phenomena occur within the runner, the energy exchange obtained from angular momentum equation only represents the work done by the driving motor on the discharge flowrate in pump mode. While it represents the net energy transferred to the rotor by the driving flowrate in reverse mode, that is the mechanical work available on the shaft when internal recirculation losses are taken into account.},
keywords = {Losses, part load, Pump, Pump as Turbine, Turbine},
pubstate = {published},
tppubtype = {inproceedings}
}
Direct and reverse operation of three radial flow turbomachines at part load conditions are investigated in order to evaluate the energy exchange between runner and fluid. Recirculation phenomena that occur at low flowrates interact with the blade passages with a net exchange momentum which has to be supplied by the impeller in pump mode, while reducing the one transmitted to the rotor by the fluid in turbine mode. Partial flow characteristic curves are also influenced in both operation modes. In order to highlight the role played by backward flows on the performances, the runnerfluid energy transfer has been evaluated from both velocity and power measurements. In particular, leakage and windage losses have been segregated and measured. The experimental results show that when recirculation phenomena occur within the runner, the energy exchange obtained from angular momentum equation only represents the work done by the driving motor on the discharge flowrate in pump mode. While it represents the net energy transferred to the rotor by the driving flowrate in reverse mode, that is the mechanical work available on the shaft when internal recirculation losses are taken into account.
1998
Ardizzon, Guido; Pavesi, Giorgio
Optimum incidence angle in centrifugal pumps and radial inflow turbines Journal Article
In: Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, vol. 212, iss. 2, pp. 97-107, 1998, ISSN: 0957-6509.
Abstract | Links | BibTeX | Tags: Incidence Angle, Incidence Angle, Optimal, Optimum, Pump, Turbine, Turbine
@article{Ardizzon1998,
title = {Optimum incidence angle in centrifugal pumps and radial inflow turbines},
author = {Guido Ardizzon and Giorgio Pavesi},
url = {http://journals.sagepub.com/doi/10.1243/0957650981536628},
doi = {10.1243/0957650981536628},
issn = {0957-6509},
year = {1998},
date = {1998-01-01},
journal = {Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy},
volume = {212},
issue = {2},
pages = {97-107},
abstract = {A theoretical method is presented for establishing the optimum incidence angle in outward- and inward-flow runners. Relative through-flow and eddy vortex are considered separately in order to examine their influence on the vane inlet conditions. The action of the counter-rotating vortex and of the blade camber is analysed and an algorithm is given for the evaluation of the optimum incidence angle. The validity of the procedure is finally verified by comparing the theoretical results with experimental observations and with numerical computations. ? IMechE 1998.},
keywords = {Incidence Angle, Incidence Angle, Optimal, Optimum, Pump, Turbine, Turbine},
pubstate = {published},
tppubtype = {article}
}
A theoretical method is presented for establishing the optimum incidence angle in outward- and inward-flow runners. Relative through-flow and eddy vortex are considered separately in order to examine their influence on the vane inlet conditions. The action of the counter-rotating vortex and of the blade camber is analysed and an algorithm is given for the evaluation of the optimum incidence angle. The validity of the procedure is finally verified by comparing the theoretical results with experimental observations and with numerical computations. ? IMechE 1998.
1995
Ardizzon, Guido; Pavesi, Giorgio
Theoretical Evaluation of the Effects of the Impeller Entrance Geometry and of the Incident Angle on Cavitation Inception in Centrifugal Pumps Journal Article
In: Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, vol. 209, iss. 1, pp. 29-38, 1995, ISSN: 20412983.
Abstract | Links | BibTeX | Tags: Incidence Angle, Pump, Turbine
@article{Ardizzon1995,
title = {Theoretical Evaluation of the Effects of the Impeller Entrance Geometry and of the Incident Angle on Cavitation Inception in Centrifugal Pumps},
author = {Guido Ardizzon and Giorgio Pavesi},
doi = {10.1243/PIME_PROC_1995_209_119_02},
issn = {20412983},
year = {1995},
date = {1995-01-01},
journal = {Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science},
volume = {209},
issue = {1},
pages = {29-38},
abstract = {A method, based on quasi three-dimensional analysis, of describing pump cavitation behaviour is proposed. Cavitation performance is related to impeller entrance design and the influence of the angle of attack of the leading edges on the flow is studied. Coefficients are derived from the pressure drop due separately to the vanes and shroud. The influence of incident angle on cavitation is shown as a function of the blade geometry and discussed. By comparison with experimental data on centrifugal pumps, it is shown that the present model can simulate the characteristics of inception cavitation at design and off-design conditions. ? 1995, Institution of Mechanical Engineers. All rights reserved.},
keywords = {Incidence Angle, Pump, Turbine},
pubstate = {published},
tppubtype = {article}
}
A method, based on quasi three-dimensional analysis, of describing pump cavitation behaviour is proposed. Cavitation performance is related to impeller entrance design and the influence of the angle of attack of the leading edges on the flow is studied. Coefficients are derived from the pressure drop due separately to the vanes and shroud. The influence of incident angle on cavitation is shown as a function of the blade geometry and discussed. By comparison with experimental data on centrifugal pumps, it is shown that the present model can simulate the characteristics of inception cavitation at design and off-design conditions. ? 1995, Institution of Mechanical Engineers. All rights reserved.
