0
Research Papers: Gas Turbines: Combustion, Fuels, and Emissions

An Experimental Study of Lean Blowout With Hydrogen-Enriched Fuels

[+] Author and Article Information
Shengrong Zhu

Turbine Innovation and Energy Research (TIER) Center, Department of Mechanical Engineering,  Louisiana State University, Baton Rouge, LA 70803szhu2@tigers.lsu.edu

Sumanta Acharya1

Turbine Innovation and Energy Research (TIER) Center, Department of Mechanical Engineering,  Louisiana State University, Baton Rouge, LA 70803acharya@me.lsu.edu

1

Corresponding author.

J. Eng. Gas Turbines Power 134(4), 041507 (Feb 01, 2012) (10 pages) doi:10.1115/1.4004742 History: Accepted July 04, 2011; Received July 04, 2011; Published February 01, 2012; Online February 01, 2012

Lean premixed combustion is widely used to achieve a better compromise between nitric oxide (NOx ) emissions and combustion efficiency (related to CO levels). However, combustor operation near the lean blowout (LBO) limit can render the flame unstable and lead to oscillations, flashback, or extinction, thereby limiting the potential range of lean combustion application. Recent interest in integrated gasification combined cycle plants and syngas combustion requires an improved understanding of the role of hydrogen on the combustion process. Therefore, in the present study, combustion of pure methane and blended methane-hydrogen with hydrogen-levels up to 80% by volume has been conducted in a swirl stabilized premixed combustor. Particle imaging velocimetry (PIV) and OH* chemiluminescence imaging have been used in this study. Results show that there is a single-ringed structure of internal recirculation zone (IRZ) in the non-reacting flow, while in the reacting flows, there is a more complex flow pattern with a two-celled IRZ structure in which the axial velocity near the center-axis is oriented downstream. As the equivalence ratio decreases, the width of IRZ decreases in methane flames while it increases in hydrogen-enriched flames, and the flame shape changes from conical to an elongated columnar shape, especially in hydrogen-enriched flames. There are two different modes of vortex breakdown observed, spiral mode in methane flames and bubble mode in hydrogen-enriched flames. These differences between the behavior of the methane-only and hydrogen-enriched flames lead to different behavior of the flame as it approaches the lean blowout. The differences in the mechanisms of LBO in pure methane and hydrogen-enriched premixed flames are examined and explained in the present study.

FIGURES IN THIS ARTICLE
<>
Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Sectional view of the burner

Grahic Jump Location
Figure 2

Axial velocity field for (a) non-reacting flow, (b) CH4 flame at Φ = 0.684, and (c) 80% hydrogen-enriched flame at Φ = 0.264

Grahic Jump Location
Figure 3

Boundaries of IRZ for (a) CH4 flames, (b) 40% H2 flames, (c) 60% H2 flames, and (d) 80% H2 flames

Grahic Jump Location
Figure 4

Instantaneous OH* distributions for CH4 flame at Φ = 0.684 (top two rows) and 80% H2 flame at Φ = 0.264 (bottom two rows). Time increases from left to right with step increments of 0.2 s.

Grahic Jump Location
Figure 5

Power spectra of OH* signal for (a) CH4 flames and (b) 80% H2 enriched flames

Grahic Jump Location
Figure 6

Normalized Vrms color contour superimposed with normalized Vmean line contour and thickened IRZ lines for CH4 flames for (a) Φ = 0.684, (b) Φ = 0.689, (c) Φ = 0.694, and (d) Φ = 0.774

Grahic Jump Location
Figure 7

Normalized Vrms color contour superimposed with normalized Vmean line contour and thickened IRZ lines for 80% H2 flames for (a) Φ = 0.264, (b) Φ = 0.268, (c) Φ = 0.340, and (d) Φ = 0.432

Grahic Jump Location
Figure 8

Normalized Vrms color contour superimposed with normalized Vmean line contour and thickened IRZ lines for non-reacting flow

Grahic Jump Location
Figure 9

Abel inverted radial distributions of averaged OH* superimposed with IRZ lines for methane flames for (a) Φ = 0.684, (b) Φ = 0.689, (c) Φ = 0.694, and (d) Φ = 0.744

Grahic Jump Location
Figure 10

Abel inverted radial distributions of averaged OH* superimposed with IRZ lines for 80% hydrogen-enriched flames for (a) Φ = 0.264, (b) Φ = 0.268, (c) Φ = 0.340, and (d) Φ = 0.432

Grahic Jump Location
Figure 11

Boundaries of IRZ (lines) and centers of reaction zones (circle symbols) for (a) CH4 flames and (b) 80% H2 flames

Grahic Jump Location
Figure 12

Hypothesis diagram for LBO mechanisms of methane and hydrogen-enriched flames

Tables

Errata

Discussions

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 Journal Articles
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