<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The article discusses the phenomenon of stator <bold>W</bold>ake/<bold>R</bold>otor cascade (W/R) interaction in a steam turbine stage, and the ability to capture it in turbine stage design calculations making use of standard numerical codes. Firstly, the W/R interaction is analysed by comparing its real, experimentally recorded course with the numerical results obtained using vortex theory models and methods. This part of the analysis ends with formulating a conclusion about stochastic nature of the W/R interaction and indicating its reason, which is the vortex structure of the stator wake. Next, a question is discussed whether and how this stochastic nature of the examined phenomenon can be taken into account in calculations of <bold>R</bold>eynolds <bold>A</bold>veraged <bold>N</bold>avier-<bold>S</bold>tokes (RANS) equations. Differences are indicated between the uniform pattern of the stator wake obtained using a RANS code and the vortex structure of the real wake. It is concluded, however, that despite these differences the RANS results correctly reflect the time-averaged course of the real W/R interaction, and the process of averaging the flow parameters on the sliding plane between stator and rotor calculation areas can be treated as sort of “numerical averaging” of different realisations of the W/R interaction.</p></abstract>

The article discusses the phenomenon of stator Wake/Rotor cascade (W/R) interaction in a steam turbine stage, and the ability to capture it in turbine stage design calculations making use of standard numerical codes. Firstly, the W/R interaction is analysed by comparing its real, experimentally recorded course with the numerical results obtained using vortex theory models and methods. This part of the analysis ends with formulating a conclusion about stochastic nature of the W/R interaction and indicating its reason, which is the vortex structure of the stator wake. Next, a question is discussed whether and how this stochastic nature of the examined phenomenon can be taken into account in calculations of Reynolds Averaged Navier-Stokes (RANS) equations. Differences are indicated between the uniform pattern of the stator wake obtained using a RANS code and the vortex structure of the real wake. It is concluded, however, that despite these differences the RANS results correctly reflect the time-averaged course of the real W/R interaction, and the process of averaging the flow parameters on the sliding plane between stator and rotor calculation areas can be treated as sort of “numerical averaging” of different realisations of the W/R interaction.

Wake-blade interaction in steam turbine stages

Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-952 Gdansk, POLAND

Polish Maritime Research

{"article-title":"Wake-blade interaction in steam turbine stages"}

The article discusses the phenomenon of stator Wake/Rotor cascade (W/R) interaction in a steam turbine stage, and the ability to capture it in turbine stage...

Wake-blade interaction in steam turbine stages

Published Online: Jul 10, 2013

Page range: 30 - 40

DOI: https://doi.org/10.2478/pomr-2013-0014

Keywords
turbine passage, secondary vortices, stochastic behaviour, CFD calculations

This content is open access.

Wake-blade interaction in steam turbine stages

Published Online: Jul 10, 2013

Page range: 30 - 40

DOI: https://doi.org/10.2478/pomr-2013-0014

Keywordsturbine passage, secondary vortices, stochastic behaviour, CFD calculations

This content is open access.

Keywords
turbine passage, secondary vortices, stochastic behaviour, CFD calculations