Borghi diagram

Keywords Borghi diagram Combustion Chemical reactions Chemical kinetics Damkohler number Flamelets Ignition Karlovitz number Mixing-controlled... 

Fig. 13.1 Borghi diagram showing the different combustion regimes. The (F) applies to premixed combustion and (N) applies to non-premixed combustion...

In summary, the Borghi diagram illustrates how a one-dimensional laminar flame front in region (1) becomes increasingly three-dimensional through the interaction between turbulence and chemistry. 

With these identifications, according to Borghi [6], one obtains a diagram with almost identical regions as for premixed combustion. In Fig. 13.1, the non-premixed regions are identified with the letter N. Note that the basic turbulence-chemistry interactions which define these regions, that is Ret =, Da = 1, and Ka = I, also define the different regions for the non-premixed flame structures. 

Figure 5.6 shows the diagram of Borghi for premixed combustion in terms of the logarithm of v /sl versus the logarithm of Z//f [15]. The lines Ret = 1, Da =, and Ka = represent boundaries between the different regimes of premixed turbulent combustion. 

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