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16.4 Solid Phase Phenomena This section contains examples that test the one-dimensional heat conduction solver in FDS, along with those that include pyrolysis. 16.4.1 Simple Heat Conduction Through a Solid Slab (heat_conduction) Analytical solutions of transient, one-dimensional heat conduction through a slab can be found in Refs. [33] and [34]. Four cases are examined here. In each, a slab of thickness L = 0.1 m is exposed on one face to an air temperature of Tg = 120 ◦ C. The other face is insulated (adiabatic). The convective heat transfer from the gas to the slab is q̇00c = h (Tg − Ts ), where h is constant, and Ts is the slab face temperature. No thermal radiation is included. Case k (W/m/K) 0.1 0.1 1.0 10.0 A B C D ρ (kg/m3 ) 100 100 1000 10000 c (kJ/kg/K) 1 1 1 1 140 140 heat_conduction_a heat_conduction_b 120 120 100 100 Temperature ( C) Temperature ( C) Bi hL/k 100 10 1 0.1 h (W/m2 /K) 100 10 10 10 80 60 40 80 60 40 20 20 0 0 0 500 1000 1500 0 2000 2000 4000 Time (s) 8000 10000 12000 14000 Time (s) 70 140 heat_conduction_d heat_conduction_c 120 60 100 Temperature ( C) Temperature ( C) 6000 80 60 40 50 40 30 20 20 10 0 0 10000 20000 30000 40000 50000 0 10000 20000 30000 Time (s) Time (s) 144 40000 50000