Research on pressure pulsation characteristics of a pump-turbine in pump mode with rotating stall: Focus on the broadband frequency

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(4)

Published: April 1, 2024

To investigate the adverse effects of rotating stalls on pressure pulsation characteristics a pump-turbine in pump mode, an unsteady numerical simulation was carried out by applying partially averaged Navier–Stokes turbulence model. The methods were carefully verified, and onset flow rate hump at performance curve heads good agreement with experimental data. stall appeared guide vane when ranged from 0.514 to 0.887 times best efficiency point (QBEP), frequency 11.7% rotational frequency. In period stall, sudden intensive channel observed named as component broadband frequency, its corresponding mechanism explained vortex evolution between adjacent blades based dynamic mode decomposition technology. There three distinct frequency: (i) intermittent occurrence cell propagated current channel, (ii) wide range varying rate, (iii) considerable amplitude, e.g., reaching 21.1%–42.2% that addition, both amplitude gradually decreased increased 0.887QBEP. This study clarified internal behaviors if occurred, which important assess stability units.

Language: Английский

---

Investigation of the effect of blade angle of Archimedes spiral hydrokinetic turbine based on hydrodynamic performance and entropy production theory

Ocean Engineering, Journal Year: 2025, Volume and Issue: 324, P. 120731 - 120731

Published: Feb. 22, 2025

Language: Английский

---

Numerical analysis of the far wake flow behind a submarine with full appendages

Proceedings of the Institution of Mechanical Engineers Part M Journal of Engineering for the Maritime Environment, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 21, 2025

Wake flow behind underwater vehicles such as submarines was widely researched with its impacts on propulsion or antisubmarine technology. Extensive research performed the near wake for hydrodynamics of propulsion, but far given less attention owing to huge challenges and expensive costs. In this study, a long-range evolution full-size Suboff submarine full appendages is numerically investigated by Delayed Detached Eddy Simulation (DDES) method, which provides reference shape design detection. Evolution vortex structures sail tail detailed, including modes horseshoe vortex, hairpin tip vortex. The diffusion along at specific speed also focused, using slice analysis vorticity velocity. When dimensionless velocity profiles in different slices are stacked up, overlay shows pretty coincident contour deficit submarine. equations range fitted orthogonal distance regression principle further application.

Language: Английский

---

A cavitation model with adaptive grid resolution capability to improve prediction performance of vortex cavitation

Ocean Engineering, Journal Year: 2025, Volume and Issue: 324, P. 120693 - 120693

Published: Feb. 24, 2025

Language: Английский

---

Analysis of internal flow characteristics and loss mechanism of Pelton turbine’s water supply component

Renewable Energy, Journal Year: 2025, Volume and Issue: unknown, P. 123135 - 123135

Published: April 1, 2025

Language: Английский

---

Analysis of hydrodynamic and loss characteristics of hydrofoil under the effect of tip clearance

Ocean Engineering, Journal Year: 2024, Volume and Issue: 316, P. 119936 - 119936

Published: Dec. 3, 2024

Language: Английский

---

An improved detached eddy simulation method for cavitation multiphase flow

Ocean Engineering, Journal Year: 2024, Volume and Issue: 313, P. 119359 - 119359

Published: Sept. 30, 2024

Language: Английский

---