Numerical Investigation of Clocking Effects on the Hydraulic Performance of Pump–Turbine in Pump Mode

Lisheng Zhang, Yongbo Li, Ming Ma, Lijun Kong, Zhenghai Huang, Lintao Xu and Bofu Wang ()
Additional contact information
Lisheng Zhang: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China
Yongbo Li: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China
Ming Ma: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China
Lijun Kong: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China
Zhenghai Huang: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China
Lintao Xu: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China
Bofu Wang: Hubei Technology Innovation Center for Smart Hydropower, Wuhan 430014, China

Energies, 2025, vol. 18, issue 16, 1-20

Abstract: This study numerically investigates clocking effects on pump–turbine hydraulic performance in pump mode. Analyzing the influence of clock position on pressure loss characteristics under three flow conditions and its correlation with internal flow. By integrating local hydraulic loss theory and vortex evolution analysis, the operational mechanism is elucidated. Key results show that the stay vane clock position significantly impacts off-design conditions, causing maximum efficiency differences of 0.855% at 0.8 Q d and 0.805% at 1.2 Q d . At the design condition, guide vane clocking position has a more pronounced effect, yielding a maximum inter-scheme efficiency difference of 0.330%. The optimal scheme positions the tongue at the guide vane trailing edge and 1/4 of the stay vane flow path, minimizing time-averaged losses and enhancing flow stability. The clocking effect alters the scale and intensity of volute dual-vortex structures, significantly increasing energy loss at vortex interfaces, with volute loss identified as the primary factor in performance variation. This work provides a theoretical foundation for applying clocking effects in pump–turbine engineering.

Keywords: pump–turbine; clocking effect; hydraulic performance; pump mode; internal flow field (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/18/16/4317/pdf (application/pdf)
https://www.mdpi.com/1996-1073/18/16/4317/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:18:y:2025:i:16:p:4317-:d:1723994

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().