How does a pre-mixed gas mixture move from the unburned to the burned zone in the two zone combustion model?
The mixture before combustion in the unburned zone is fully mixed. This consists of unburned fuel, air and residuals. During combustion the unburned mixture moves to the burned zone. The mixture moving to the burned zone is proportional to the amount of mass burned until it reaches 100% burned. i.e. fraction of burned mass X total mass. If you want to know how much of the mixture has burned, you should use plot #147 Normalized Fuel Mass Burned.
