Abstract
The effects of velocity boundary conditions on the structure of methane-air nonpremixed counterflow flames were investigated by two-dimensional numerical simulation. Two low global strain rates, 12 s−1 and 20 s−1, were considered for comparison with measurements. Buoyancy was confirmed to have strong effects on the flame structure at a low global strain rate. It was shown that the location where a top hat velocity profile was imposed is sensitive to the flame structure, and that the computed temperature along the centerline agrees well with the measurements when plug flow was imposed at the inner surface of the screen nearest the duct exit.
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Abbreviations
- ag :
-
Global strain rate
- D:
-
Duct diameter
- L:
-
Duct separation
- rv :
-
Velocity ratio, Vo/VF
- s:
-
Distance between duct exit and location where top hat velocity profile is imposed
- T:
-
Temperature
- V:
-
Mean velocity in duct
- O:
-
Oxidizer
- F:
-
Fuel
References
Chelliah, H. K., Law, C. K., Ueda, T., Smoke, M. D. and Williams, F. A., 1990, “An Experimental and Theoretical Investigation of the Dilution, Pressure and Flow-Field Effects on the Extinction Condition of Methane-Air-Nitrogen Diffusion Flames,”Proc. 23rd Symposium on Combustion, pp. 503–511.
Floyd, J. E., McGrattan, K. B. and Baum, H. R., 2001, “A Mixture Fraction Combustion Model for Fire Simulation Using CFD,”Proc. Int’l Conf on Engineered Fire Protection Design, pp. 279–290.
Lee, K. Y., Cha, D. J., Hamins, A. and Pun, I. K., 1996, “Heat Relaease Mechanisms in Inhibited Laminar Counterflow flames,”Combustion and Flames, Vol. 105, pp. 27–40.
Maruta, K., Yoshida, M., Guo, H., Ju, V. and Niioka, T., 1998, “Extinction of Low-Stretched Diffusion Flame in Microgravity,”Combustion and Flames, Vol. 112, pp. 181 -187.
McGrattan, K. B., Baum, H. R., Rehm, R. G., Hamins, A., Forney, G. P., Floyd, J. E., Hostikka, S., 2001, Fire Dynamics Simulator Technical Reference Guide V. 2, National Institute of Standards and Technology, Gaithersburg, MD (also http://fire.nist.gov/fds/).
Park, W. C., 2001a, “An Evaluation of a Direct Numerical Simulation for Counterflow Diffusion Flames,” Submitted to Korea Institute for Industrial Safety Journal (in Korean).
Park, W. C., Hamins, A. and McGrattan, 2001, “Two-Dimensional Simulation of Diluted Nonpremixed Counterflow Flames,” Submitted to 29th Int’l Symposium on Combustion.
Puri, I. K. and Hamins, A., 2001, “A Numerical Investigation of Radiative Effects in Near-Extinction Methane-Air Nonpremixed Flames,” Submitted to Combustion and Flame.
Seshadri, K. and Williams, F. A., 1978, “Laminar Flow Between Parallel Plates with Injection of a Reactant at High Reynolds Number,”Int’l J. Heat Mass Transfer, Vol. 21, pp. 251–253.
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Park, WC., Hamins, A. Investigation of velocity boundary conditions in counterflow flames. KSME International Journal 16, 262–269 (2002). https://doi.org/10.1007/BF03185178
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DOI: https://doi.org/10.1007/BF03185178