Markstein number

If the Markstein number is positive, then the flame is thermo-diffusively stable. 

The first analytical estimation of the value of the Markstein number in the presence of realistic gas expansion was given by Clavin and Williams [8]. In the approximation of a one-step Arrhenius reaction with a high activation energy P, they found fhe following expression for Ma ... 

The Lewis number, Le, is that of the deficient species (fuel or oxidant) in the mixture. In their analysis, Clavin and Williams used the simplifying approximation that the shear viscosity, the Lewis number, and the Prandtl numbers are all temperature-independent. They also showed that, at least for weak flame stretch and curvature, the change in local flame speed due to stretch and curvature is described by the same Markstein number ... 

Ma is the Markstein number, of order unity, which for temperature-dependent diffusivities is now given by... 

S.G. Davis, J. Quinard, and G. Searby. Markstein numbers in counterflow, methane- and propane-air flames A computational study. Combustion and Flame, 130 123-136, 2002. 

G. Searby and J. Quinard. Direct and indirect measurements of Markstein numbers of premixed flames. Combustion and Flame, 82(3-4) 298-311, 1990. 

J.M. Truffaut and G. Searby. Experimental study of the Darrieus-Landau instability on an inverted- V flame and measurement of the Markstein number. Combustion Science and Technology, 149 35-52, 1999. 

INFLUENCE OF MARKSTEIN NUMBER ON THE PARAMETRIC ACOUSTIC INSTABILITY... 

Another aim is an examination of the influence of the Markstein number on the effect of the secondary pyroacoustic instability, associated with the development of transverse acoustic waves and pulsating cells on the flame [4, 5]. In addition, laminar-flame speeds measured during the stage of a nearly flat surface (Stage B in Fig. 7.1) are compared with those reported in the literature. 

Figure 7.6 Markstein number variation with equivalence ratio for propane-air (J) and methane-air (2) mixtures.

Muller, U.C., M. Bollig, and N. Peters. 1997. Approximations for burning velocities and Markstein numbers for lean hydrocarbon and methanol flames. Combustion Flame 108 349. 

Lindstedt Have your results on Markstein number been compared to work done earlier in this area ... 

It was shown that mixtures with similar flame speeds can have very different behaviors due to their level of susceptibility to stretch effects as characterized through the Markstein number by Aldredge s group at the University of California, Davis (Chapter 7). 

The characteristic dimensional parameter Lm takes into account the flame curvature effect on the burning velocity. The higher its absolute value, the stronger the curvature effect is. The Markstein length relation to the laminar flame thickness S = dSu, where - the laminar flame velocity, is known as the Markstein number Ma = Lyild. Table 1.1 [15] presents the Markstein length for hydrogen-air mixtures at 298 K and 0.1 MPa... 

L.-K. Tseng, M.A. Ismail, G.M. Faeth, Laminar burning velocities and Markstein numbers of hydrocarbon/air flames. Combust. Flame 95, 410-426 (1993)... 

Markstein length Characteristic dimensional parameter Lm taking into account a flame curvature effect on a combustion velocity. The greater is an absolute value of this parameter, the more the curvature effect is. A ratio of a Markstein length Lm to a laminar flame thickness d = alS, where -combustion laminar velocity, is called the Markstein number Ma = Lm/S. 

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