Laminar flame speed determination

Wu, C.K. and Law, C.K., On the determination of laminar flame speeds from stretched flames, Proc. Combust. Inst.,... 

Hirasawa, T., Sung, C.J., Yang, Z., Joshi, A., Wang, H., and Law, C.K., Determination of laminar flame speeds of fuel blends using digital particle image velocimetry Ethylene, M-butane, and toluene flames, Proc. Combust. Inst., 29,1427, 2002. 

Vagelopoulos, C.M. and Egolfopoulos, F.N., Direct experimental determination of laminar flame speeds, Proc. Comb. Inst., 27 513, 1998. 

The initial theoretical analyses for the determination of the laminar flame speed fell into three categories thermal theories, diffusion theories, and comprehensive theories. The historical development followed approximately the same order. 

The simple physical approaches proposed by Mallard and Le Chatelier [3] and Mikhelson [14] offer significant insight into the laminar flame speed and factors affecting it. Modem computational approaches now permit not only the calculation of the flame speed, but also a determination of the temperature profile and composition changes throughout the wave. These computational approaches are only as good as the thermochemical and kinetic rate values that form their database. Since these approaches include simultaneous chemical rate processes and species diffusion, they are referred to as comprehensive theories, which is the topic of Section C3. 

To determine the laminar flame speed and flame structure, it is now possible to solve by computational techniques the steady-state comprehensive mass, species, and energy conservation equations with a complete reaction mechanism for the fuel-oxidizer system which specifies the heat release. The numerical... 

The Mallard-Le Chatelier development for the laminar flame speed permits one to determine the general trends with pressure and temperature. When an overall rate expression is used to approximate real hydrocarbon oxidation kinetics experimental results, the activation energy of the overall process is found to be quite high—of the order of 160kJ/mol. Thus, the exponential in the flame speed equation is quite sensitive to variations in the flame temperature. This sensitivity is the dominant temperature effect on flame speed. There is also, of course, an effect of temperature on the diffusivity generally, the dif-fusivity is considered to vary with the temperature to the 1.75 power. 

Vagelopoulos, C. M., F.N. Egolfopoulos, and C.K. Law. 1994. Further considerations on the determination of laminar flame speeds with the counterflow twin-flame technique. 25th Symposium (International) on Combustion Proceedings. Pittsburgh, PA The Combustion Institute. 1341-47. 

C.K. Wu and C.K. Law. On the Determination of Laminar Flame Speeds from Stretched Flames. Proc. Combust. Inst., 20 1941-1949,1984. 

A consequence of the equivalence of the two problems is that any of the procedures discussed in Section 5.3 for determining the laminar flame-speed eigenvalue A of equation (5-45) can be applied without modification for finding A as a function of t., a, and P [defined in equation (5-44)] in the present problem. In using these procedures, one should recognize that co(t) is given by equation (5-43) only for t > ct = 0 for t < t-. Results... 

The laminar flame speeds of blends of tetrachloromethane with methane in air at ambient temperature and pressure have been experimentally determined. A detailed kinetic model previously employed for MeCl, CH2CI2, and CHCI3 combustion was expanded to include additional pathways pertinent to tetrachloromethane combustion and predicts the laminar flame speeds reasonably well. ... 

Jomaas G, Zheng XL, Zhu DL, Law CK (2005) Experimental determination of counterflow ignition temperatures and laminar flame speeds of C2-C3 hydrocarbons at atmospheric and elevated pressures. Proc Combust Inst 30 193-200... 

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