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.
Ardizzon, Guido; Pavesi, Giorgio
Modelli di Perdita nelle Turbomacchine, Previsione delle Prestazioni e Verifica Sperimentale Proceedings Article
In: 54° Congresso Nazionale ATI, pp. 1397-1408, SGE - Padova, 1999.
Abstract | BibTeX | Tags: Losses, Off-Design, Pump, Turbine, Turbomachinery
@inproceedings{Ardizzon1999,
title = {Modelli di Perdita nelle Turbomacchine, Previsione delle Prestazioni e Verifica Sperimentale},
author = {Guido Ardizzon and Giorgio Pavesi},
year = {1999},
date = {1999-01-01},
urldate = {1999-01-01},
booktitle = {54° Congresso Nazionale ATI},
pages = {1397-1408},
publisher = {SGE - Padova},
abstract = {A performance prediction procedure is presented toghere with a review of loss models given in literature. Some of the original loss correlations have been modified so as to make them more directly applicable to low flow rate operation. At off-design conditions the mismatching of impeller and volute causes to vary velocity and pressure round the periphery of the impeller. This contributes significantly to the magnitude of the energy losses in the volute. The non-uniformity of the flow in the volute is taken into account by an unsteady one-dimensional method. Notwithstanding the several simplifying assumptions the results of the head capacity curve calculation agree well with the experimental results almost all over the range of operating conditions. Finelly the model supplies a basis for selecting the of parameters for optimal design of pumps in which both the maximum efficiency and the head shape are important design parameter.},
keywords = {Losses, Off-Design, Pump, Turbine, Turbomachinery},
pubstate = {published},
tppubtype = {inproceedings}
}
A performance prediction procedure is presented toghere with a review of loss models given in literature. Some of the original loss correlations have been modified so as to make them more directly applicable to low flow rate operation. At off-design conditions the mismatching of impeller and volute causes to vary velocity and pressure round the periphery of the impeller. This contributes significantly to the magnitude of the energy losses in the volute. The non-uniformity of the flow in the volute is taken into account by an unsteady one-dimensional method. Notwithstanding the several simplifying assumptions the results of the head capacity curve calculation agree well with the experimental results almost all over the range of operating conditions. Finelly the model supplies a basis for selecting the of parameters for optimal design of pumps in which both the maximum efficiency and the head shape are important design parameter.
