Publication detail

Proper Orthogonal Decomposition of Pressure Fields in a Draft Tube Cone of the Francis (Tokke) Turbine Model

ŠTEFAN, D. RUDOLF, P.

Original Title

Proper Orthogonal Decomposition of Pressure Fields in a Draft Tube Cone of the Francis (Tokke) Turbine Model

Type

conference paper

Language

English

Original Abstract

The simulations of high head Francis turbine model (Tokke) are performed for three operating conditions - Part Load, Best Efficiency Point (BEP) and Full Load using software Ansys Fluent R15 and alternatively OpenFOAM 2.2.2. For both solvers the simulations employ Realizable k-epsilon turbulence model. The unsteady pressure pulsations of pressure signal from two monitoring points situated in the draft tube cone and one behind the guide vanes are evaluated for all three operating conditions in order to compare frequencies and amplitudes with the experimental results. The computed velocity fields are compared with the experimental ones using LDA measurements in two locations situated in the draft tube cone. The proper orthogonal decomposition (POD) is applied on a longitudinal slice through the draft tube cone. The unsteady static pressure fields are decomposed and a spatio-temporal behavior of modes is correlated with amplitude-frequency results obtained from the pressure signal in monitoring points. The main application of POD is to describe which modes are related to an interaction between rotor (turbine runner) and stator (spiral casing and guide vanes) and cause dynamic flow behavior in the draft tube. The numerically computed efficiency is correlated with the experimental one in order to verify the simulation accuracy.

Keywords

POD, CFD, OpenFOAM, Fluent, Francis turbine

Authors

ŠTEFAN, D.; RUDOLF, P.

RIV year

2015

Released

6. 1. 2015

Publisher

IOP Publishing

ISBN

1742-6596

Periodical

Journal of Physics: Conference Series

Year of study

579

Number

1

State

United Kingdom of Great Britain and Northern Ireland

Pages from

1

Pages to

14

Pages count

14

URL

Full text in the Digital Library

BibTex

@inproceedings{BUT111311,
  author="David {Štefan} and Pavel {Rudolf}",
  title="Proper Orthogonal Decomposition of Pressure Fields in a Draft Tube Cone of the Francis (Tokke) Turbine Model",
  booktitle="Journal of Physics: Conference Series",
  year="2015",
  journal="Journal of Physics: Conference Series",
  volume="579",
  number="1",
  pages="1--14",
  publisher="IOP Publishing",
  doi="10.1088/1742-6596/579/1/012002",
  issn="1742-6596",
  url="http://iopscience.iop.org/1742-6596/579/1/012002/"
}