0

Full Content is available to subscribers

Subscribe/Learn More  >

On the Prediction and Theory of the Temperature Increase of Low Pressure Last Stage Moving Blades During Low Volume Flow Conditions, and Limiting it Through Steam Extraction Methods

[+] Author Affiliations
Adam Beevers, Said Havakechian, Benjamin Megerle

Alstom Power (Switzerland), Baden, Switzerland

Paper No. GT2014-25456, pp. V01BT27A011; 13 pages
doi:10.1115/GT2014-25456
From:
  • ASME Turbo Expo 2014: Turbine Technical Conference and Exposition
  • Volume 1B: Marine; Microturbines, Turbochargers and Small Turbomachines; Steam Turbines
  • Düsseldorf, Germany, June 16–20, 2014
  • Conference Sponsors: International Gas Turbine Institute
  • ISBN: 978-0-7918-4558-5
  • Copyright © 2014 by Alstom Technologie AG

abstract

During extreme low volume flow conditions, the last stages of a low pressure steam turbine operate in ventilation conditions that can cause a significant temperature increase of critical regions of the last stage moving blade. Under some conditions, the blade temperature may rise above a safe operating temperature, requiring the machine to be shut down. Limiting the heating effect on the last stage moving blade increases the allowable operating range of the low pressure turbine. One common method is to spray water droplets into the low pressure exhaust. As the length of last stage moving blades continues to increase, this method reaches its limit of practical operating effectiveness due to the amount of water required and its impact on the erosion of the LSB.

An investigation into complimentary solutions to limit the temperature increase was conducted using CFD. An appropriate CFD setup was chosen from a sensitivity study on the effect of geometry, mesh density, turbulence model and time dependency. The CFD results were verified against steam turbine data from a test facility. The proposed complimentary solutions to limit the temperature increase include low temperature steam extraction, targeted for critical regions of the moving blade. From the test turbine and CFD results, the drivers of the temperature increase during ventilation conditions are identified and described.

Copyright © 2014 by Alstom Technologie AG

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In