Detail publikace

Study of the internal flow field in a pump-as-turbine (PaT): Numerical investigation, overall performance prediction model and velocity vector analysis

ŠTEFAN, D. ROSSI, M. HUDEC, M. RUDOLF, P. NIGRO, A. RENZI, M.

Originální název

Study of the internal flow field in a pump-as-turbine (PaT): Numerical investigation, overall performance prediction model and velocity vector analysis

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

angličtina

Originální abstrakt

This work presents a detailed analysis of the three-dimensional flows in a Pump-as-Turbine (PaT). The flow field is studied through URANS simulations and a velocity vector analysis. Moreover, a prediction model is used to forecast the performance of the PaT. The results of these methodologies were validated using experimental results. Flow rate and head at Best Efficiency Point (BEP) in turbine mode were 27% and 41% higher than the ones in pump mode, respectively; the mechanical efficiency was 4% lower. To give a fluid flow interpretation of this behaviour, velocity triangles in turbine mode were analytically calculated, as well as numerically evaluated. The analytically identified PaT flow rate at BEP is in agreement with CFD and measurements. Only small differences appear, which might be explained by three reasons: i) the real flow angle is influenced by the finite number of blades and their thickness, ii) the PaT leading edge has a sharp ending since the impeller is designed to operate only in pump mode and iii) tapering of the meridional cross-section from volute to impeller. While close to the BEP the mechanical efficiency is flat, a sensible drop caused by flow detachments and swirling flows was detected at part-load.

Klíčová slova

Pump–as–turbine; Unsteady CFD simulations; Experimental data; Performance prediction model; Velocity triangles

Autoři

ŠTEFAN, D.; ROSSI, M.; HUDEC, M.; RUDOLF, P.; NIGRO, A.; RENZI, M.

Vydáno

13. 4. 2020

Nakladatel

Elsevier

ISSN

0960-1481

Periodikum

RENEWABLE ENERGY

Ročník

156

Stát

Spojené království Velké Británie a Severního Irska

Strany od

158

Strany do

172

Strany počet

14

URL

https://www.sciencedirect.com/science/article/pii/S0960148120305188?via%3Dihub

BibTex

@article{BUT163459,
  author="David {Štefan} and Mosé {Rossi} and Martin {Hudec} and Pavel {Rudolf} and Alessandra {Nigro} and Massimiliano {Renzi}",
  title="Study of the internal flow field in a pump-as-turbine (PaT): Numerical investigation, overall performance prediction model and velocity vector analysis",
  journal="RENEWABLE ENERGY",
  year="2020",
  volume="156",
  number="0",
  pages="158--172",
  doi="10.1016/j.renene.2020.03.185",
  issn="0960-1481",
  url="https://www.sciencedirect.com/science/article/pii/S0960148120305188?via%3Dihub"
}