Flow Characteristics of Preliminary Shutdown and Startup Sequences for a Model Counter-Rotating Pump-Turbine
Artikel i vetenskaplig tidskrift, 2021

Pumped Hydropower Storage (PHS) is the maturest and most economically viable technology for storing energy and regulating the electrical grid on a large scale. Due to the growing amount of intermittent renewable energy sources, the necessity of maintaining grid stability increases. Most PHS facilities today require a geographical topology with large differences in elevation. The ALPHEUS H2020 EU project has the aim to develop PHS for flat geographical topologies. The present study was concerned with the initial design of a low-head model counter-rotating pump-turbine. The machine was numerically analysed during the shutdown and startup sequences using computational fluid dynamics. The rotational speed of the individual runners was decreased from the design point to stand-still and increased back to the design point, in both pump and turbine modes. As the rotational speeds were close to zero, the flow field was chaotic, and a large flow separation occurred by the blades of the runners. Rapid load variations on the runner blades and reverse flow were encountered in pump mode as the machine lost the ability to produce head. The loads were less severe in the turbine mode sequence. Frequency analyses revealed that the blade passing frequencies and their linear combinations yielded the strongest pulsations in the system.

hydropower

startup

pump-turbine

pumped hydro storage

low-head

counter-rotating

transient sequences

OpenFOAM

shutdown

Författare

Jonathan Fahlbeck

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Håkan Nilsson

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Saeed Salehi

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Energies

1996-1073 (ISSN)

Vol. 14 12

Augmenting grid stability through Low-head Pumped Hydro Energy Utilization & Storage (ALPHEUS)

Europeiska kommissionen (EU) (883553), 2020-04-01 -- 2024-03-31.

Drivkrafter

Hållbar utveckling

Styrkeområden

Energi

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

Ämneskategorier

Energisystem

Strömningsmekanik och akustik

DOI

10.3390/en14123593

Mer information

Senast uppdaterat

2021-07-08