Turbulent flames propagation

The balanced equation for turbulent kinetic energy in a reacting turbulent flow contains the terms that represent production as a result of mean flow shear, which can be influenced by combustion, and the terms that represent mean flow dilations, which can remove turbulent energy as a result of combustion. Some of the discrepancies between turbulent flame propagation speeds might be explained in terms of the balance between these competing effects. 

F. A. WiUiams, in J. H. S. Lee and C. M. Cuirao, eds., EaminarFlame Instability and Turbulent Flame Propagation, In FuelAirExplosions, University of Waterloo Press, Waterloo, Ontario, Canada, 1982. 

Lee, J. H. S., R. Knystautas, and C. K. Chan. 1984. Turbulent flame propagation in obstacle-filled tubes. 20th Symp. (Int.) on Combustion, pp. 1663-1672. The Combustion Institute, Pittsburgh, PA. 

Moen, I. O., M. Donato, R. Knystautas, J. H. Lee, and H. Gg. Wagner. 1980b. Turbulent flame propagation and acceleration in the presence of obstacles. Progress in Astronautics and Aeronautics. 75 33-47, AIAA Inc., New York. 

Moen, 1. O., J. H. S. Lee, B. H. Hjertager, K. Fuhre, and R. K. Eckhoff. 1982. Pressure development due to turbulent flame propagation in large-scale methane-air explosions. Comb, and Flame. 47 31-52. 

The only computational approach found in the literature to modeling flash-hre radiation is that of Raj and Emmons (1975), who modeled a flash fire as a two-dimensional, turbulent flame propagating at a constant speed. The model is based on the following experimental observations ... 

Tabaczynski, R. Trinker, F. H., and Shannon, B. A. S., Further refinement and validation of a turbulent flame propagation model for spark-ignition engines. Combustion and Flame, 39, 111-121, 1980. 

C. M. Muller, H. Breitbach, and N. Peters, Partially premixed turbulent flame propagation in jet flames, Proc. Combust. Inst. 25 1099-1106,1994. 

Samaniego, J.M. and Mantel, T, Fundamental mechanisms in premixed turbulent flame propagation via flame-vortex interactions Part I Experiment, Combust. Flame, 118, 537, 1999. 

Lee, J.H., Knystautas, R., and Chan, C., Turbulent flame propagation in obstacle-filled tubes, Proc. Combust. Inst., 20, 1663, 1984. 

The parameters Pt T, T) and A are used to construct the PDF in such a way that the model predictions for well-defined conditions correspond to experimental measurements. For constructing a proper temperature PDF, the PPDF method was applied to the problem of planar turbulent flame propagation. 

Figure 15.1 Schematic diagram of the Taylor-Couette apparatus used for studies of turbulent flame propagation...

Cheng, R. K., and I. C. Shepherd. 1991. The influence of burner geometry on premixed turbulent flame propagation. Combustion Flame 85 7-26. 

Aldredge, R. G. 1996. A novel flow reactor for the study of heat-loss effects on turbulent flame propagation. International Communications Heat Mass Transfer 22 1173-79. 

An alternative view [36] is that if l/d becomes too small, then extinctions of laminar flamelets are reflected in extinction of the turbulent flame. According to this idea, there is a region to the upper left in Figure 10.5 in which turbulent flame propagation cannot occur. It seems physically that phenomena of this type may pertain to confined turbulent flows in reactors of small volume, where they would reflect influences of turbulence properties... 

Chapter 9 represents an effort to provide a unified and tutorial presentation of the broad field of the theory of combustion instabilities. The length of the chapter attests to the vastness of the field and to the progress that has been made therein in recent years. The final section of this chapter, on the theory of instabilities of premixed flames, is basic to analyses of premixed turbulent flame propagation and also has a bearing on aspects of flammability limits. 

A complete model would embrace the cylinder flow, turbulence, flame propagation, and gas reaction, and, if they occur, autoignitions at hot spots and the associated interactive pressure pulses. No such model has been achieved, although there have been partial successes in marrying autoignition to engine combustion models. As will be shown later, the accurate modelling of pressure pulses presents formidable problems. 

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