Description of the Ignition Process

Ignition involves a reaction process of the oxidizer and fuel fragments that are produced at the surface of an energetic material that produces the heat needed to achieve steady-state burning. The surface temperature is first increased by additional heat provided externally by means of an igniter. When the temperature on or just beneath 

One assumes that the oxidizer component, O, and the fuel component, F, react to produce reaction product, P, along the burning direction, x. The reaction is expressed by 

When the ignition process occurs under conditions of constant pressure, the momentum equation is expressed by 

Equations (13.7)-(13.13) are used to evaluate the ignition processes of energetic materials with appropriate initial and boundary conditions. In general, the conditions in the thermal field for ignition are given by 

In the solid phase, well below the regressing surface, the second and third terms of Eq. (13.10) may be neglected because no chemical reaction occurs and no irradiation energy penetrates through the regressing surface. Thus, Eq. (13.10) is expressed by 

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