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

Numerical and Experimental Studies on a Syngas-Fired Ultra Low NOx Combustor

[+] Author and Article Information
S. Krishna

Clean Combustion Research Center,
King Abdullah University of
Science and Technology,
Thuwal 23955, Saudi Arabia
e-mail: krishna.seshagiri@kaust.edu.sa

R. V. Ravikrishna

Professor
Combustion and Spray Laboratory,
Department of Mechanical Engineering,
Indian Institute of Science,
Bengaluru 560012, Karnataka, India
e-mail: ravikris@mecheng.iisc.ernet.in

Contributed by the Combustion and Fuels Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received January 14, 2016; final manuscript received April 28, 2017; published online June 21, 2017. Assoc. Editor: Ajay Agrawal.

J. Eng. Gas Turbines Power 139(11), 111502 (Jun 21, 2017) (13 pages) Paper No: GTP-16-1015; doi: 10.1115/1.4036945 History: Received January 14, 2016; Revised April 28, 2017

Simulations and exhaust measurements of temperature and pollutants in a syngas-fired model trapped vortex combustor for stationary power generation applications are reported. Numerical simulations employing Reynolds-averaged Navier–Stokes (RANS) and large eddy simulations (LES) with presumed probability distribution function (PPDF) model were also carried out. Mixture fraction profiles in the trapped vortex combustor (TVC) cavity for nonreacting conditions show that LES simulations are able to capture the mean mixing field better than the RANS-based approach. This is attributed to the prediction of the jet decay rate and is reflected on the mean velocity magnitude fields, which reinforce this observation at different sections in the cavity. Both RANS and LES simulations show close agreement with the experimentally measured OH concentration; however, the RANS approach does not perform satisfactorily in capturing the trend of velocity magnitude. LES simulations satisfactorily capture the trend observed in exhaust measurements which is primarily attributed to the flame stabilization mechanism. In the exhaust measurements, mixing enhancement struts were employed, and their effect was evaluated. The exhaust temperature pattern factor was found to be poor for baseline cases, but improved with the introduction of struts. NO emissions were steadily below 3 ppm across various flow conditions, whereas CO emissions tended to increase with increasing momentum flux ratios (MFRs) and mainstream fuel addition. Combustion efficiencies ∼96% were observed for all conditions. The performance characteristics were found to be favorable at higher MFRs with low pattern factors and high combustion efficiencies.

Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Singhal, A. , and Ravikrishna, R. V. , 2011, “ Single Cavity Trapped Vortex Combustion Dynamics—Part 1: Experiments,” Int. J. Spray Combust. Dyn., 3(1), pp. 23–44. [CrossRef]
Singhal, A. , and Ravikrishna, R. V. , 2011, “ Single Cavity Trapped Vortex Combustion Dynamics—Part-2: Simulations,” Int. J. Spray Combust. Dyn., 3(1), pp. 45–52. [CrossRef]
Agarwal, K. K. , and Ravikrishna, R. V. , 2011, “ Experimental and Numerical Studies in a Compact Trapped Vortex Combustor: Stability Assessment and Augmentation,” Combust. Sci. Technol., 183(12), pp. 1308–1327. [CrossRef]
Agarwal, K. K. , and Ravikrishna, R. V. , 2012, “ Validation of a Modified Eddy Dissipation Concept Model for Stationary and Non-Stationary Diffusion Flames,” Combust. Sci. Technol., 184(2), pp. 151–164. [CrossRef]
Agarwal, K. K. , and Ravikrishna, R. V. , 2013, “ Mixing Enhancement in a Compact Trapped Vortex Combustor,” Combust. Sci. Technol., 185(3), pp. 363–378. [CrossRef]
Krishna, S. , and Ravikrishna, R. V. , 2015, “ Optical Diagnostics of Fuel-Air Mixing and Vortex Formation in a Cavity Combustor,” Exp. Therm. Fluid Sci., 61, pp. 163–176. [CrossRef]
Krishna, S. , and Ravikrishna, R. V. , 2015, “ Quantitative OH PLIF Diagnostics of Syngas and Methane Combustion in a Cavity Combustor,” Combust. Sci. Technol., 187(11), pp. 1661–1682. [CrossRef]
Jin, Y. , Li, Y. , Xiaomin, H. , Zhang, J. , Jiang, B. , Wu, Z. , and Song, Y. , 2014, “ Experimental Investigations on Flow Field and Combustion Characteristics of a Model Trapped Vortex Combustor,” Appl. Energy, 134, pp. 257–269. [CrossRef]
Nemitallah, M. A. , and Mohamed, A. H. , 2013, “ Experimental and Numerical Investigations of an Atmospheric Diffusion Oxy-Combustion Flame in a Gas Turbine Model Combustor,” Appl. Energy, 111, pp. 401–415. [CrossRef]
Zeinivand, H. , and Bazdidi-Tehrani, F. , 2012, “ Influence of Stabilizer Jets on Combustion Characteristics and NOx Emission in a Jet-Stabilized Combustor,” Appl. Energy, 92, pp. 348–360. [CrossRef]
Zhang, R. C. , Fan, W. J. , Shi, Q. , and Tan, W. L. , 2014, “ Combustion and Emissions Characteristics of Dual-Channel Double-Vortex Combustion for Gas Turbine Engines,” Appl. Energy, 130, pp. 314–325. [CrossRef]
Arghode, V. K. , and Gupta, A. K. , 2013, “ Role of Thermal Intensity on Operational Characteristics of Ultra-Low Emission Colourless Distributed Combustion,” Appl. Energy, 111, pp. 930–956. [CrossRef]
Li, J. , Zhao, Z. , Kazakov, A. , Chaos, M. , Dryer, F. L. , and Scire, J. J., Jr. , 2009, “ A Comprehensive Kinetic Mechanism for CO, CH2O, and CH3OH Combustion,” Int. J. Chem. Kinet., 39(3), pp. 109–136. [CrossRef]
Cuoci, A. , Frassoldati, A. , Ferraris, G. B. , Faravelli, T. , and Ranzi, E. , 2007, “ The Ignition, Combustion and Flame Structure of Carbon Monoxide/Hydrogen Mixtures—Note 2: Fluid Dynamics and Kinetic Aspects of Syngas Combustion,” Int. J. Hydrogen Energy, 32(15), pp. 3486–3500. [CrossRef]
Krishna, S. , Pramanik, S. , and Ravikrishna, R. V. , 2013, “ Numerical Modelling of a Turbulent Non-Premixed CO/H2/N2 Flame,” 23rd National Conference on IC Engines and Combustion (NCICEC), Surat, India, Dec. 13–16.
Kemenov, K. A. , Wang, H. , and Pope, S. B. , 2009, “ Grid Resolution Effects on LES of a Piloted Methane-Air Flame,” Sixth U.S. National Combustion Meeting, Ann Arbor, MI, May 17–20, pp. 146–159. https://tcg.mae.cornell.edu/pubs/Kemenov_WP_09.pdf
Boudier, G. , Gicquel, L. Y. M. , Poinsot, T. , Bissieres, D. , and Berat, C. , 2009, “ Effect of Mesh Resolution on Large Eddy Simulation of Reacting Flows in Complex Geometry Combustors,” Combust. Flame, 155(1–2), pp. 196–214.
Barlow, R. S. , Fiechtner, G. J. , Carter, C. D. , and Chen, J.-Y. , 2000, “ Experiments of the Scalar Structure of Turbulent CO/H2/N2 Jet Flames,” Combust. Flame, 120(4), pp. 549–569. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Single cavity TVC combustor rig and schematic with dimensions

Grahic Jump Location
Fig. 2

Grid independence results for RANS and LES simulations

Grahic Jump Location
Fig. 3

Stations for comparison of simulations and experimental results

Grahic Jump Location
Fig. 4

CO mass fraction and velocity magnitude contours for case 1 (MFR 4.5)

Grahic Jump Location
Fig. 5

Mixture fraction profiles at different sections for MFR 4.5, 1.1, and 0.3

Grahic Jump Location
Fig. 6

Velocity magnitude profiles at Sec. 2 (cavity center) for MFR 4.5, 1.1, and 0.3

Grahic Jump Location
Fig. 7

OH concentration contours for case 1 (MFR 4.5)

Grahic Jump Location
Fig. 8

OH concentration contours for case 2 (MFR 1.1)

Grahic Jump Location
Fig. 9

OH concentration profiles at different Secs. 2 and 3 for MFR 4.5, 1.1, and 0.3

Grahic Jump Location
Fig. 10

Velocity magnitude profiles at Sec. 3 for MFR 4.5, 1.1 and 0.3

Grahic Jump Location
Fig. 11

Thermocouple measurement locations and flow enhancement struts

Grahic Jump Location
Fig. 12

Baseline temperature distribution

Grahic Jump Location
Fig. 13

Temperature distribution with mainstream premixing and struts

Grahic Jump Location
Fig. 14

Broadband luminosity images for MFR 4.5 for baseline, premixing, and struts cases

Grahic Jump Location
Fig. 15

Comparison of temperature and pollutant emission at the exit plane for experiments and simulations

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