A highly adaptive three dimensional hybrid vortex method for inviscid flows and helically symmetric vortex equilibria [PDF]
, 2012 This thesis is concerned with three-dimensional vortex dynamics, in particular the modelling of vortex structures in an inviscid context. We are motivated by the open problem of regularity of the inviscid equations, i.e.
Lucas, Daniel
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Effect of Fins on the Internal Flow Characteristics in the Draft Tube of a Francis Turbine Model
Energies, 2020 Undesirable flow phenomena in Francis turbines are caused by pressure fluctuations induced under conditions of low flow rate; the resulting vortex ropes with precession in the draft tube (DT) can degrade performance and increase the instability of ...
Seung-Jun Kim +6 more
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Diffuser Shape Optimization Using Adjoint Solver [PDF]
MATEC Web of ConferencesShape optimization of a diffuser with vortex generator on the inlet that mimics the impeller of a Francis turbine was performed. The optimization is based on the use of the adjoint solver in ANSYS Fluent.
Pham Jakub, Rudolf Pavel
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Machines, 2022 Small vessels operating in coastal waters are susceptible to propeller failure because of the entanglement of marine debris. Secondary accidents such as the injury of divers may also occur when removing entangling material.
Antony John Nyongesa +8 more
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Suppressing the Vortex Rope Oscillation and Pressure Fluctuations by the Air Admission in Propeller Hydro-Turbine Draft Tube [PDF]
Journal of Applied Fluid Mechanics, 2023 For the purpose of automatic generation control (AGC), a portion of the propeller hydro-turbine units in China is adjusted to operate within a restricted range of 75%-85% load using computer-controlled AGC strategies.
H. Wu +9 more
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The numerical simulation of the rope vortex creation and the possibilities of its control
Journal of Physics: Conference Series, 2021 Abstract The rope vortex is a phenomena which can be observed in many hydraulic machines, especially turbines and pump–turbines. Its creation is based on a non uniform velocity profile characterized by high value of the circumferential component.
P Szulc +3 more
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Coupling Mechanisms Between Vortex Rope Evolution and Cavitation Within the Draft Tube of Pump-turbines [PDF]
Journal of Applied Fluid MechanicsA technique integrating numerical simulations with experimental observations was hereby employed to elucidate the flow instability mechanisms during transient processes in pump-turbines, and a reversible pump-turbine was investigated for in-depth ...
L. Xin, Q. Li, S. Zhang
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Numerical simulations of a flux rope ejection [PDF]
, 2015 Coronal mass ejections (CMEs) are the most violent phenomena observed on the Sun. One of the most successful models to explain CMEs is the flux rope ejection model, where a magnetic flux rope is expelled from the solar corona after a long phase along ...
Pagano, P. +6 more
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Wake structure and kinematics in the vortex ring state [PDF]
, 2009 High-resolution computational simulations of the vortical wake of a rotor operating both near to and within the vortex ring state have been conducted using Brown's vorticity transport model.
Brown, R.E., Ahlin, G.A.
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Damping force of air acting on vibrating elevator rope
Mechanical Engineering Journal, 2021 This paper describes the vibration damping characteristics of elevator ropes acted on by air. High-rise buildings sometimes resonate during earthquakes, and the elevator ropes in the building may swing significantly as a result. The vibration analysis of
Raichi TAKUMI, Hideo UTSUNO
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