Applications to Extinction for Diffusive Burning

Let us examine the 1300 °C criterion as a condition of flame extinction in diffusive burning to see how these critical conditions depend on oxygen and external radiation. After all, these two parameters - oxygen and radiation - are the two significant variables that make most solids bum. We will look to some data for anchoring this application. 

The flame radiation is taken as zero since the flame size diminishes. 

The properties needed are taken from Reference [28] for consistency and are given in Table 9.4. The heat of gasification of wood is approximated since it is unsteady and charring. 

In order to apply this extinction criterion, it will further be assumed that the steady state form of Equation (9.112) applies with no char, no water and no backface loss. As a consequence the burning rate can be described as 

Apply Equation (9.109) for these pure materials under conditions as steady, no char and no water  

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