Full Content is available to subscribers

Subscribe/Learn More  >

Scale Model Testing Towards Primary Air Optimization of a CFB Boiler

[+] Author Affiliations
Tyler Hughes, Sastry Munukutla, Stephen Idem

Tennessee Tech University, Cookeville, TN

John Kang

JEA - Electric Generation, Jacksonville, FL

Daniel Porter

Rayonier Performance Fibers, Fernandina Beach, FL

Paper No. POWER2013-98039, pp. V001T05A003; 10 pages
  • ASME 2013 Power Conference
  • Volume 1: Fuels and Combustion, Material Handling, Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines, Generators and Auxiliaries; Plant Operations and Maintenance
  • Boston, Massachusetts, USA, July 29–August 1, 2013
  • Conference Sponsors: Power Division
  • ISBN: 978-0-7918-5605-5
  • Copyright © 2013 by ASME


Primary air flow is supplied to the wind box of a 300 MW CFB boiler by means of three primary air ducts connected to a common plenum. A flow rate measurement is performed in each duct using an Annubar flow meter. Due to the tight configuration of the piping and the associated turbulence, the measured flows in the three ducts were not consistent, resulting in improper air flow distribution in the boiler. A primary air duct flow study was performed in an effort to improve measurement accuracy, which will lead to improved combustion efficiency and low load cycling by allowing precision air flow control in the furnace.

The objective of this project was to employ a 1/10th scale model test to determine the best method to improve the flow upstream of each Annubar flow meter. Tests were conducted with room temperature air at several flow rates generated by a centrifugal fan. Reynolds number independence was achieved in the tests. Appropriate dimensionless Grashof and Prandtl number scaling was used to extrapolate the scale model tests to the high temperature conditions prevalent in the unit. Flow visualization and measurements using a five-hole directional velocity probe were performed. It was determined that mounting 50% open area screens in the primary air duct of the scale model had the effect of significantly reducing both yaw and pitch angles across the Annubar measurement plane. A complimentary benefit was that the velocity profiles in the flow direction were notably flattened by the addition of the screens. Furthermore the performance of the Annubar flow meters could be improved if the measurement plane was moved further upstream of the opposed blade flow control damper.

Copyright © 2013 by ASME



Interactive Graphics


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

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