Numerical study of the flame stability of premixed methane–air combustion in a combined porous-free flame burner

Abstract

Premixed methane–air combustion process within a combined porous-free flame burner was investigated numerically in the present study. The burner consisted of a perforated porous ceramic pellet forming combination of submerged and free flame zones. Nonequilibrium thermal condition between the gas and solid phases was implemented and governing equations were solved in a two-dimensional model using finite volume method. Detailed chemistry based on reduced GRI 3.0 mechanism with 41 reaction steps and 16 species including NOx mechanisms was utilized to simulate the combustion processes and pollutant emissions. In order to investigate the validation of the implemented numerical model, the burner was manufactured and tested. The predicted results were consistent with the experimental data. Comparison of the combined porous-free flame burner with porous burner showed that the flame stability limits of the combined burner were higher than those of porous burner. Multimode heat transfer within the porous medium was perused and the effect of heat recirculation on the flame stabilization was discussed. Investigation of the effect of pore density on the flame stabilization showed that the lower pore densities were desirable in order to improve the flame stability limits. Pollutant emission analysis proved that the NO concentration increased with increasing the equivalence ratio while the minimum quantity of CO concentration was evaluated at an equivalence ratio of 0.6.

Keywords

Combined porous-free flame burner flame stabilization heat recirculation equivalence ratio pore density pollutant emission

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References

Hashimoto

Yamasaki

Takeno

. An excess enthalpy flame stabilized in ceramic tubes Flames, lasers, and reactive systems (A 84-28387 12-25), New York: American Institute of Aeronautics and Astronautics Inc., 1983, pp. 57–77.

Kotani

Behbahani

Takeno

. An excess enthalpy flame combustor for extended flow ranges. Symp (Int) Combust 1985; 20: 2025–2033.

Bouma

De Goey

LPH

. Premixed combustion on ceramic foam burners. Combust Flame 1999; 119: 133–143.

Mathis

Jr Ellzey

. Flame stabilization, operating range, and emissions for methane/air porous burner. Combust Sci Technol 2003; 155: 825–839.

Barra

Ellzey

. Heat recirculation and heat transfer in porous burners. Combust Flame 2004; 137: 230–241.

Barra

Diepvens

Ellzey

et al.

Numerical study of the effects of material properties on flame stabilization in a porous burner. Combust Flame 2003; 134: 369–379.

Sathe

Peck

Tong

. Flame stabilization and multimode heat transfer in inert porous media: a numerical study. Combust Sci Technol 1990; 70: 93–109.

Hsu

Evans

Howell

. Experimental and numerical investigation of premixed combustion within nonhomogeneous porous inert media. Combust Sci Technol 1993; 90: 149–172.

Trimis

Durst

. Combustion in a porous medium-advances and applications. Combust Sci Technol 1996; 121: 153–168.

10.

Shakiba

Ebrahimi

Shams

et al.

Effects of foam structure and material on the performance of premixed porous ceramic burner. Proc IMechE, Part A: J Power and Energy 2015; 229: 176–191.

11.

Bakry

Al Salaymeh

Al Muhtaseb

et al.

Adiabatic premixed combustion in a gaseous fuel porous inert media under high pressure and temperature: novel flame stabilization technique. Fuel 2011; 90: 647–658.

12.

Gao

Feng

et al.

Methane/air premixed combustion in a two-layer porous burner with different foam materials. Fuel 2014; 115: 154–161.

13.

Gao

Feng

et al.

Premixed combustion in a porous burner with different fuels. Combust Sci Technol 2015; 187: 489–504.

14.

Weakley CK, Greenberg SJ, Kendall RM, et al. Development of surface-stabilized fuel injectors with sub-3 PPM NOx emissions. In: Presented at the 2002 International Joint Power Generation Conference, ASME Paper IJPGC2002-26088, Phoenix, AZ, 24–26 June 2002.

15.

Greenberg SJ, McDougald NK and Arellano LO. Full-scale demonstration of surface-stabilized fuel injectors for sub-three PPM NOx emissions. In: Presented at the 2004 ASME Turbo Expo, ASME Paper GT2004-53629, Vienna, Austria, 14–17 June 2004.

16.

Hashemi SA, Nikfar M and Ghorashi SA. Numerical study of the effect of thermal boundary conditions and porous medium properties on the combustion in a combined porous-free flame burner. Proc IMechE, Part A: J Power and Energy. Epub ahead of print 2018. DOI: 10.1177/0957650918755549.

17.

Frenklach M, Wang H, Goldenberg M, et al. GRI-MechAn optimized detailed chemical reaction mechanism for methane combustion. GRI Topical Report 95/0058, 1995.

18.

Taylor JR. An introduction to error analysis the study of uncertainties in physical measurements. 2nd ed. Sausalito, California: University Science Books, 1997.

19.

Lemos

MJS

. Turbulence in porous media: modeling and applications, Amsterdam: Elsevier, 2006, pp. 384–384.

20.

Macdonald

El-Sayed

Mow

et al.

Flow through porous media Ergun equation revisited. Ind Eng Chem Fund 1979; 18: 199–208.

21.

Younis

Viskanta

. Experimental determination of the volumetric heat transfer coefficient between stream of air and ceramic foam. Int J Heat Mass Transf 1993; 36: 1425–1434.

22.

Trimis

Durst

Pickänecker

et al.

Porous medium combustor versus combustion systems with free flames, Nuremburg: University Erlangen, 2002.

23.

Mohamad AA. Combustion in porous media: fundamentals and applications. Transport Phenomena in Porous Media III 2005; 287–304.

24.

Modest

. Radiative heat transfer, New York: McGraw-Hill, 1993.

25.

Pope

Yang

. An investigation of the accuracy of manifold methods and splitting schemes in the computational implementation of combustion chemistry. Combust Flame 1998; 112: 16–32.

26.

Chai

Lee

Patankar

. Finite volume method for radiation heat transfer. J Thermophys Heat Transf 1994; 8: 419–425.

27.

Patankar

Spalding

. A calculation procedure for heat, mass and momentum transfer in three-dimensional parabolic flows. Int J Heat Mass Transf 1972; 15: 787–1806.

28.

Kee RJ, Grcar JF, Smooke MD, et al. A fortran program for modeling steady laminar one-dimensional premixed flames. SAND85-8240, Sandia National Laboratories Report, 1985.

29.

Howell

Buckius

. Fundamentals of engineering thermodynamics, New York: McGraw-Hill, 1992, pp. 888–888.

30.

. Combustion theory and technology, Beijing: China Electric Power Press, 2011.

31.

Baiquan

Huaming

Chaoqun

et al.

Combustion characteristics of low concentration coal mine methane in divergent porous media burner. Int J Mining Sci Technol 2014; 24: 671–676.

32.

Kennedy

Saveliev

Bingue

et al.

Filtration combustion of a methane wave in air for oxygen enriched and oxygen-depleted environments. Proc Combust Inst 2002; 29: 835–841.