PyroSim software was used to establish the combustion behavior of polymers in the cone calorimeter test, the char yield, the effects of
thermal conductivity and the specific heat capacity of the char layer on the combustion process of polymer were analyzed. The results
show that, the heat release rate curves show a single peak while the char yield is 0%. The heat release rate curves have three peaks when
the char yield is larger than 0%. The charring of polymer significantly influences the shape of heat release rate curves. The heat release
rate decreased with the increasing of char yield of polymer. Moreover, the heat release rate of charred polymer improved with the thermal
conductivity of char layer. Moreover, the specific heat capacity of char layer plays no role in the heat release rate of polymer and the
combustion behavior of polymer.