All

What are you looking for?

All
Projects
Results
Organizations

Quick search

  • Projects supported by TA ČR
  • Excellent projects
  • Projects with the highest public support
  • Current projects

Smart search

  • That is how I find a specific +word
  • That is how I leave the -word out of the results
  • “That is how I can find the whole phrase”

Experimental investigation of swirl number influence on spiral vortex structure dynamics

The result's identifiers

  • Result code in IS VaVaI

    <a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F21%3APU141174" target="_blank" >RIV/00216305:26210/21:PU141174 - isvavai.cz</a>

  • Alternative codes found

    RIV/61388998:_____/21:00545835

  • Result on the web

    <a href="https://iopscience.iop.org/article/10.1088/1755-1315/774/1/012085" target="_blank" >https://iopscience.iop.org/article/10.1088/1755-1315/774/1/012085</a>

  • DOI - Digital Object Identifier

    <a href="http://dx.doi.org/10.1088/1755-1315/774/1/012085" target="_blank" >10.1088/1755-1315/774/1/012085</a>

Alternative languages

  • Result language

    angličtina

  • Original language name

    Experimental investigation of swirl number influence on spiral vortex structure dynamics

  • Original language description

    The hydraulic turbines are recently forced to operate far away from the optimal conditions in order to balance fluctuations in electricity generation. In case of Francis, pump and propeller turbines, using only single control component of guide vanes, it means that in regions where the high residual swirl enters the draft tube, the flow is decelerated and convenient conditions for the vortex rope development are created. Such flow conditions are considered to be the triggering mechanism for occurrence of different forms of vortex structures in the Francis turbine draft tube, e.g. spiral or straight vortex rope at part load or full load respectively. Independently on the vortex rope shape the unsteady pressure fields develop producing periodic stress on turbine components and possibly resulting in noise, blade cracks, runner lift, power swing, etc. To study and mimic such flow conditions, a simplified device of vortex generator apparatus is employed. Thanks to its design, the vortex generator enables to change the ratio between fluxes of axial momentum and tangential moment of momentum of generated swirl. Then, the behavior of vortex structure changes in a similar way as the flow rate variation in the draft tube of Francis turbine. For above mentioned reasons the unsteady cavitating spiral vortex is experimentally studied using both high speed video record and particle image velocimetry (PIV). The main focus is on change of vortex dynamics regarding to the swirl number variation. The proper orthogonal decomposition (POD) together with the classical fast Fourier transformation (FFT) are employed to extract dominant modes and frequencies from experimental data.

  • Czech name

  • Czech description

Classification

  • Type

    D - Article in proceedings

  • CEP classification

  • OECD FORD branch

    20301 - Mechanical engineering

Result continuities

  • Project

    <a href="/en/project/EF16_026%2F0008392" target="_blank" >EF16_026/0008392: Computer Simulations for Effective Low-Emission Energy Engineering</a><br>

  • Continuities

    P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Others

  • Publication year

    2021

  • Confidentiality

    S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Data specific for result type

  • Article name in the collection

    IOP Conference Series-Earth and Environmental Science

  • ISBN

  • ISSN

    1755-1307

  • e-ISSN

  • Number of pages

    10

  • Pages from-to

    012085-012085

  • Publisher name

    IOP Publishing

  • Place of publication

    neuveden

  • Event location

    Lausanne

  • Event date

    Mar 21, 2021

  • Type of event by nationality

    WRD - Celosvětová akce

  • UT code for WoS article

    000712043400085