Effect of Pressure, Environment Temperature, Jet Velocity and Nitrogen Dilution on the Liftoff Characteristics of a N2-in-H2 Jet Flame in a Vitiated Co-flow

A. North; M. Magar; J. Y. Chen; R. Dibble; A. Gruber

doi:10.18321/ectj178

Authors

A. North 50B Hesse Hall, Department of Mechanical Engineering, University of California Berkeley, Berkeley, CA 94720-1740, USA
M. Magar Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
J. Y. Chen 50B Hesse Hall, Department of Mechanical Engineering, University of California Berkeley, Berkeley, CA 94720-1740, USA
R. Dibble 50B Hesse Hall, Department of Mechanical Engineering, University of California Berkeley, Berkeley, CA 94720-1740, USA
A. Gruber SINTEF Energy Research, 7465 Trondheim, Norway

DOI:

https://doi.org/10.18321/ectj178

Keywords:

hydrogen, jet flames, turbulent combustion, flame propagation, autoignition

Abstract

The CO₂ emission prevention advantage of generating power with high hydrogen content fuels using gas turbines motivates an improved understanding of the ignition behavior of hydrogen in premixed and partially premixed environments. Hydrogen rich fueled flame stability is sensitive to operating conditions, including environment pressure, temperature, and jet velocity. Furthermore, when premixed or partially premixed operation is needed for nitric oxide emissions reduction, a diluent, such as nitrogen, is often added in allowing fuel/air mixing prior to combustion. Thus, the concentration of the diluent added is an additional independent variable on which flame stability dependence is needed. The focus of this research is on characterizing the dependence of hydrogen jet flame stability on environment temperature, pressure, jet velocity and diluent concentration by determining the dependence of the liftoff height of lifted flames on these 4 independent parameters. Nitrogen is used as the diluent due to its availability and effectiveness in promoting liftoff. A correlation modeling the liftoff height dependence on operating conditions is developed which emphasizes the factors that bear the greatest impact on ignition behavior.

References

[1]. A. North, D.J. Frederick, J.Y. Chen, R.W. Dibble, A. Gruber, Stability and Liftoff of a N2-in-H2 Jet Flame in a Vitiated Co-flow at Atmospheric Pressure, pending approval from The Eurasian Chemico-Technological Journal
(Submitted September, 2014).

[2]. K.M. Lyons, Prog. Energy Combust. Sci. 33 (2007) 211-231.

[3]. W.M. Pitts, Proc. Combust. Inst. 22 (1988) 809-816.

[4]. N. Peters, Turbulent Combustion, Cambridge University Press, Cambridge, U.K., 2000, 237–261.

[5]. U. Maas, J. Warnatz, Combust. Flame, 74 (1988) 53–69.

[6]. G. Smith et al., http://www.me.berkeley.edu/gri_mech/

[7]. J. Warnatz, U. Maas, W.F. Ames (publisher): IMACS Transactions on Scientific Computing, Numerical and Applied Mathematics, 88 (1989) 151.

[8]. C.J. Montgomery, C.R. Kaplan, E.S. Oran, Proc. Combust. Inst. 27 (1998) 1175–1182.

[9]. S. McAllister, J.Y. Chen, A.C. Fernandez-Pello, Fundamentals of Combustion Processes, Springer, New York, USA, 2011 149–151.

[10]. G.Z. Damkӧhler, Electrochem. 46 (1940) 601–626.

[11]. A.D. Birch, D.R. Brown, M.G. Dodson, J. Fluid Mech. 88 (1978) 431–449.