Publication detail

Stability of the Steady Flow in Rotationally Symmetrical Domain

POCHYLÝ, F. RUDOLF, P. HABÁN, V. KOUTNÍK, J. KRÜGER, K.

Czech title

Stabilita stacionárního proudění v rotačně symetrické oblasti

English title

Stability of the Steady Flow in Rotationally Symmetrical Domain

Type

journal article - other

Language

en

Original abstract

Perturbation analysis with a linear approach of the flow in cylindrical domain was carried out in this paper. Analysis is based on Euler equations for inviscid fluid and continuity equation in rotating frame of reference. Eigen mode shapes of velocities visualize the flow patterns and eigen mode shapes of the cavitating vortex rope show origin of the elliptical vortex rope cross-section. Investigation confirms that boundary conditions have dominant effect on steady flow stability. Results indicate that careful design of the runner and the draft tube can lead to reduction of the instability consequences or to shifting the instability to different operational ranges.

Czech abstract

Byla provedena analýza stability lineárního problému v rotačně symetrické oblasti, vycházející z Eulerovy rovnice a rovnice kontinuity v rotujícím souřadném systému. Výsledné vlastní tvary kmitu vizualizují vznik eliptického tvaru kavitujícího vírového copu. Analýza potvrdila dominantní vliv okrajových podmínek na stabilitu proudění. Je zřejmé, že vhodný návrh oběžného kola a sací trouby může nestabilitu potlačit nebo ji vymezit do jiné provozní oblasti.

English abstract

Perturbation analysis with a linear approach of the flow in cylindrical domain was carried out in this paper. Analysis is based on Euler equations for inviscid fluid and continuity equation in rotating frame of reference. Eigen mode shapes of velocities visualize the flow patterns and eigen mode shapes of the cavitating vortex rope show origin of the elliptical vortex rope cross-section. Investigation confirms that boundary conditions have dominant effect on steady flow stability. Results indicate that careful design of the runner and the draft tube can lead to reduction of the instability consequences or to shifting the instability to different operational ranges.

Keywords in Czech

vír, stabilita

Keywords in English

Swirl, stability, rotationally symmetrical, eigen value, cylinder, draft tube, elliptical

RIV year

2007

Released

24.10.2007

Publisher

Politechnica University of Timisoara

Location

Timisoara

ISSN

1224-6077

Journal

Scientific Bulletin of the "Politehnica" University of Timisoara

Volume

52

Number

6

Pages from–to

93–100

Pages count

8

BIBTEX


@article{BUT43906,
  author="František {Pochylý} and Pavel {Rudolf} and Vladimír {Habán} and Jiří {Koutník} and Klaus {Krüger},
  title="Stability of the Steady Flow in Rotationally Symmetrical Domain",
  journal="Scientific Bulletin of the "Politehnica" University of Timisoara",
  year="2007",
  volume="52",
  number="6",
  month="October",
  pages="93--100",
  publisher="Politechnica University of Timisoara",
  address="Timisoara",
  issn="1224-6077"
}