Introduction to Fire Dynamics | Ch. 6 | Eq. 6.32

Time to Ignition (Thermally Thick Solids)

Calculates the time to ignition for thermally thick solids using Drysdale's equation 6.32.

Reference

Drysdale, D., 2011. Introduction to fire dynamics. 3rd ed. Wiley.

Equations

t_{ig} = \dfrac{\pi}{4} \cdot k \cdot \rho \cdot c \cdot \left( T_{ig} - T_o \right)^{2} \cdot \dfrac{1}{\dot{Q}''_{R} ^{2}}

Thermal conductivity ( k ) — W/(m \cdot K)

Density ( \rho ) — kg/m^{3}

Specific heat capacity ( c ) — J/(kg \cdot K)

Ignition temperature ( T_{ig} ) — ^{\circ}C

Initial temperature ( T_o ) — ^{\circ}C

Radiant heat flux ( \dot{Q}''_{R} ) — W/m^{2}