Check the CCL for your combustion calculation. For each domain, the combustion model section might read as follows:
In dom1:
FLUID MODELS:
COMBUSTION MODEL:
Eddy Dissipation Model Coefficient B = 0.5
Extinction Temperature = 5000[K]*(1-fcomb1)+700[K]*fcomb1
Option = Eddy Dissipation
END
In dom2:
FLUID MODELS:
COMBUSTION MODEL:
Eddy Dissipation Model Coefficient B = 0.5
Extinction Temperature = 5000[K]*(1-fcomb2)+700[K]*fcomb2
Option = Eddy Dissipation
END
In dom3:
FLUID MODELS:COMBUSTION MODEL:
Eddy Dissipation Model Coefficient B = 0.5
Extinction Temperature = 5000[K]*(1-fcomb3)+700[K]*fcomb3
Option = Eddy Dissipation
END
Finally, in sparks:
FLUID MODELS:
COMBUSTION MODEL:
Eddy Dissipation Model Coefficient B = 0.5
Extinction Temperature = 5000[K]*(1-fcombs)+700[K]*fcombs
Option = Eddy Dissipation
END
The expression fcombs = fcomb1 + fcomb2 + fcomb3 should be added to the CEL section.