Publication detail

Model of Pressure Pulsations in Hydraulic Turbine Draft Tube Based on Linearized Rayleigh-Plesset Equation

RUDOLF, P. HABÁN, V. POCHYLÝ, F.

English title

Model of Pressure Pulsations in Hydraulic Turbine Draft Tube Based on Linearized Rayleigh-Plesset Equation

Type

Paper in proceedings (conference paper)

Language

en

Original abstract

Vortex rope appears in hydraulic turbine draft tube for partial load operation. This rope can, for certain sigma values, cavitate and contain saturated water vapour. Cavitating vortex rope is cause of pressure pulsations and effects dynamics of the whole turbine unit. Time behaviour of the spherical cavitating bubble is described by well-known Rayleigh-Plesset equation. This contribution presents derivation of the Rayleigh-Plesset equation for infinitely long cylindrical cavity imitating vortex rope. Linearized form of this equation accompanied by continuity equation and force equillibrium equation create basis for transfer matrix of the draft tube with cavitating vortex rope. Paper discusses ideas, steps of the derivation, but also necessary assumptions and simplifications leading to this new model. The final transfer matrix includes effect of the vortex rope volume change and can be included into the system of transfer matrices describing behaviour of the turbine unit with penstock.

Keywords in English

draft tube, cavitation, Rayleigh-Plesset equation, transfer matrix

Released

2006-06-28

Location

Barcelona (Spain)

Book

Proceedings of abstracts "International Meeting of the Work Group Cavitation and Dynamic Problems in Hydraulic Machienry and Systems

Pages from–to

45–

Pages count

1

BIBTEX


@inproceedings{BUT24570,
  author="Pavel {Rudolf} and Vladimír {Habán} and František {Pochylý}",
  title="Model of Pressure Pulsations in Hydraulic Turbine Draft Tube Based on Linearized Rayleigh-Plesset Equation",
  booktitle="Proceedings of abstracts {"}International Meeting of the Work Group Cavitation and Dynamic Problems in Hydraulic Machienry and Systems",
  year="2006",
  pages="1",
  address="Barcelona (Spain)"
}