Publication detail
Assessment of Specific Speed Influence on Pump-as-Turbine Operation
ŠTEFAN, D. HUDEC, M. ROSSI, M. NIGRO, A. RENZI, M. POCHYLÝ, F. BEZDÍČEK, J. RUDOLF, P.
Czech title
Posouzení vlivu specifických otáček na provoz čerpadla v turbínovém režimu
English title
Assessment of Specific Speed Influence on Pump-as-Turbine Operation
Type
article in a collection out of WoS and Scopus
Language
en
Original abstract
Pumps operating in reverse mode, often named Pumpas-Turbines (PaTs), are gaining interest in small-scale hydropower applications. Due to low investment costs and simple design, this technology is considered a good alternative to typical turbines. PaTs are mainly used in energy recovery applications, especially in drinking water pipeline systems where they replace Pressure Reducing Valves (PRVs). This work presents the assessment of three different centrifugal pumps used in reverse mode. The goal is to compare the PaTs’ performance by investigating machines having different specific speeds, namely a pump with very low specific speed nq = 9, a pump with a common value of specific speed nq = 35, and a pump with relatively high specific speed nq = 90. Measurements, as well as results from CFD simulations, are presented to verify the usability of each of the pump, and quantify the effect of specific speed on PaTs’ performance in reverse mode operation. In particular, not only integral values and characteristic curves are compared, but also flow patterns at different operating points, which are origin of hydraulic losses and other important features (e.g., the shift of the Best Efficiency Point (BEP) for pump and turbine modes) are presented and discussed.
English abstract
Pumps operating in reverse mode, often named Pumpas-Turbines (PaTs), are gaining interest in small-scale hydropower applications. Due to low investment costs and simple design, this technology is considered a good alternative to typical turbines. PaTs are mainly used in energy recovery applications, especially in drinking water pipeline systems where they replace Pressure Reducing Valves (PRVs). This work presents the assessment of three different centrifugal pumps used in reverse mode. The goal is to compare the PaTs’ performance by investigating machines having different specific speeds, namely a pump with very low specific speed nq = 9, a pump with a common value of specific speed nq = 35, and a pump with relatively high specific speed nq = 90. Measurements, as well as results from CFD simulations, are presented to verify the usability of each of the pump, and quantify the effect of specific speed on PaTs’ performance in reverse mode operation. In particular, not only integral values and characteristic curves are compared, but also flow patterns at different operating points, which are origin of hydraulic losses and other important features (e.g., the shift of the Best Efficiency Point (BEP) for pump and turbine modes) are presented and discussed.
Keywords in English
pump as turbine; specific speed; energy recovery
Released
09.11.2022
Publisher
TU Wien
Location
Wien
Book
Proceedings of conference ViennaHydro 2022
Pages from–to
1–12
Pages count
12
BIBTEX
@inproceedings{BUT182728,
author="David {Štefan} and Martin {Hudec} and Mosé {Rossi} and Alessandra {Nigro} and Massimiliano {Renzi} and František {Pochylý} and Jiří {Bezdíček} and Pavel {Rudolf},
title="Assessment of Specific Speed Influence on Pump-as-Turbine Operation",
booktitle="Proceedings of conference ViennaHydro 2022",
year="2022",
month="November",
pages="1--12",
publisher="TU Wien",
address="Wien"
}