Research Papers: Heat and Mass Transfer

Impacts of Dilution on Hydrogen Combustion Characteristics and NOx Emissions

[+] Author and Article Information
P. R. Resende

Department of Control and Automation,
Institute of Science and Technology,
São Paulo State University (UNESP),
São Paulo 18087-180, Brazil
e-mail: resende@sorocaba.unesp.br

Alexandre Afonso

Department of Mechanical Engineering,
Transport Phenomena Research Centre (CEFT),
University of Porto,
Porto 4200-465, Portugal
e-mail: aafonso@fe.up.pt

Carlos Pinho

Department of Mechanical Engineering,
Transport Phenomena Research Centre (CEFT),
University of Porto,
Porto 4200-465, Portugal
e-mail: ctp@fe.up.pt

Mohsen Ayoobi

Division of Engineering Technology,
College of Engineering,
Wayne State University,
Detroit, MI 48108
e-mail: mohsen.ayoobi@wayne.edu

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received February 14, 2018; final manuscript received October 1, 2018; published online November 16, 2018. Assoc. Editor: Yuwen Zhang.

J. Heat Transfer 141(1), 012003 (Nov 16, 2018) (6 pages) Paper No: HT-18-1090; doi: 10.1115/1.4041623 History: Received February 14, 2018; Revised October 01, 2018

Combustion characteristics at small scales have been studied continuously due to the potential applications in portable power devices. It is known that heat release impacts at small scales result in different flame behavior as compared to conventional scales. The impacts of geometry, stoichiometry, flow rates, wall temperatures, etc., are widely studied in the literature. However, dilution impacts still need to be further studied due to its important role on controlling the flame behavior and subsequent pollutants emissions at these scales. In this work, premixed hydrogen/air combustion is simulated at an axis-symmetric microchannel (with diameter D = 0.8 mm and length L = 10 mm), where detailed chemical kinetics are implemented in simulations (32 species and 173 reactions). The heat transfer on the wall is considered by imposing a hyperbolic temperature profile on the wall, where the wall temperature increases from 300 K at the inlet to 1300 K at the outlet. With this setup, a range of equivalence ratios including a typical fuel-lean regime (ϕ = 0.7), stoichiometric regime (ϕ = 1.0), and two cases at an ultra-rich regime (ϕ = 2.0 and ϕ = 3.0) are investigated. For each equivalence ratio, excess dilution (using N2) is introduced to the mixture, and its impact is compared with other cases. With that, the impacts of dilution variations on the combustion characteristics of premixed hydrogen/air are investigated for different equivalence ratios. More specifically, several incidents such as flame dynamics, flame stabilization, extinctions, and NOx emissions are studied for the aforementioned operating conditions.

Copyright © 2019 by ASME
Your Session has timed out. Please sign back in to continue.


Ayoobi, M. , and Schoegl, I. , 2017, “ Numerical Analysis of Flame Instabilities in Narrow Channels: Laminar Premixed Methane/Air Combustion,” Int. J. Spray Combust. Dyn., 9(3), pp. 155–171.
Ju, Y. , and Maruta, K. , 2011, “ Microscale Combustion: Technology Development and Fundamental Research,” Prog. Energy Combust. Sci., 37(6), pp. 669–715. [CrossRef]
Hua, J. , Wu, M. , and Kumar, K. , 2005, “ Numerical Simulation of the Combustion of Hydrogen/Air Mixture in Micro-Scaled Chambers—Part I: Fundamental Study,” Chem. Eng. Sci., 60(13), pp. 3497–3506. [CrossRef]
Hua, J. , Wu, M. , and Kumar, K. , 2005, “ Numerical Simulation of the Combustion of Hydrogen-Air Mixture in Micro-Scaled Chambers—Part II: CFD Analysis for a Micro-Combustor,” Chem. Eng. Sci., 60(13), pp. 3507–3515. [CrossRef]
Li, J. , Chou, S. , Yang, W. , and Li, Z. , 2009, “ A Numerical Study on Premixed Micro-Combustion of ch4/Air Mixture: Effects of Combustor Size, Geometry and Boundary Conditions on Flame Temperature,” Chem. Eng. J., 150(1), pp. 213–222. [CrossRef]
Aikun, T. , Jianfeng, P. , Xia, S. , and Hong, X. , 2011, “ Numerical Simulation Study of Premixed Hydrogen-Oxygen Combustion Process in Micro-Scale Rectangular Channel,” International Conference on Computer Distributed Control and Intelligent Environmental Monitoring, Changsha, China, Feb. 19–20, pp. 520–524.
Li, J. , Chou, S. K. , Li, Z. W. , and Yang, W. M. , 2008, “ A Comparative Study of h2-Air Premixed Flame in Micro Combustors With Different Physical and Boundary Conditions,” Combust. Theory Modell., 12(2), pp. 325–347. [CrossRef]
Miao, H. , Ji, M. , Jiao, Q. , Huang, Q. , and Huang, Z. , 2009, “ Laminar Burning Velocity and Markstein Length of Nitrogen Diluted Natural Gas/Hydrogen/Air Mixtures at Normal, Reduced and Elevated Pressures,” Int. J. Hydrogen Energy, 34(7), pp. 3145–3155. [CrossRef]
Kishore, V. R. , Muchahary, R. , Ray, A. , and Ravi, M. , 2009, “ Adiabatic Burning Velocity of H2–O2 Mixtures Diluted With CO2–N2–Ar,” Int. J. Hydrogen Energy, 34(19), pp. 8378–8388. [CrossRef]
Nakahara, M. , Abe, F. , Tokunaga, K. , and Ishihara, A. , 2015, “ Effect of Dilution Gas on Burning Velocity of Hydrogen-Premixed Meso-Scale Spherical Laminar Flames,” Proc. Combust. Inst., 35(1), pp. 639–646. [CrossRef]
Li, H.-M. , Li, G.-X. , Sun, Z.-Y. , Zhou, Z.-H. , Li, Y. , and Yuan, Y. , 2016, “ Investigation on Dilution Effect on Laminar Burning Velocity of Syngas Premixed Flames,” Energy, 112, pp. 146–152. [CrossRef]
Duan, J. , and Liu, F. , 2017, “ Laminar Combustion Characteristics and Mechanism of Hydrogen/Air Mixture Diluted With N2+H2O,” Int. J. Hyd. Energy, 42(7), pp. 4501–4507. [CrossRef]
Alipoor, A. , and Mazaheri, K. , 2016, “ Combustion Characteristics and Flame Bifurcation in Repetitive Extinction-Ignition Dynamics for Premixed Hydrogen-Air Combustion in a Heated Micro Channel,” Energy, 109, pp. 650–663. [CrossRef]
Cuoci, A. , Frassoldati, A. , Faravelli, T. , and Ranzi, E. , 2013, “ A Computational Tool for the Detailed Kinetic Modeling of Laminar Flames: Application to C2H4/CH4 Coflow Flames,” Combust. Flame, 160(5), pp. 870–886. [CrossRef]
Ranzi, E. , Frassoldati, A. , Grana, R. , Cuoci, A. , Faravelli, T. , Kelley, A. , and Law, C. , 2012, “ Hierarchical and Comparative Kinetic Modeling of Laminar Flame Speeds of Hydrocarbon and Oxygenated Fuels,” Prog. Energy Combust. Sci., 38(4), pp. 468–501. [CrossRef]
Pizza, G. , Frouzakis, C. E. , Mantzaras, J. , Tomboulides, A. G. , and Boulouchos, K. , 2008, “ Dynamics of Premixed Hydrogen/Air Flames in Microchannels,” Combust. Flame, 152(3), pp. 433–450. [CrossRef]
Maruta, K. , Kataoka, T. , Kim, N. I. , Minaev, S. , and Fursenko, R. , 2005, “ Characteristics of Combustion in a Narrow Channel With a Temperature Gradient,” Proc. Combust. Inst., 30(2), pp. 2429–2436. [CrossRef]


Grahic Jump Location
Fig. 1

Schematic illustration of the computational domain and the temperature profile that is imposed on the upper wall

Grahic Jump Location
Fig. 2

Heat release rate (top-half of each contour plot) and elevated temperature (bottom-half of each contour plot) contours in selected domains: (a) Contour plots at fuel-lean (ϕ = 0.7) and stoichiometric (ϕ = 1.0) conditions, (b) contour plots at ultra fuel-rich conditions (ϕ = 2.0 and ϕ = 3.0), and (c) color scales corresponding to the contour plots of Figs. 2(a) and 2(b)

Grahic Jump Location
Fig. 3

NOx emissions, total integrated heat release rates and maximum gas temperatures against dilution amounts



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