Numerical simulation of pyrolysis of PMMA involving surface and in-depth absorption

The effects of absorption models on the gasification process of PMMA exposed to an incident heat flux were investigated. A numerical one-dimension model was established to analyze the influence of absorption mode, including surface and in-depth absorption, on pyrolysis process of clear PMMA sample which was exposed to an external heat flux. The corresponding cone calorimetry tests in nitrogen atmosphere that were conducted by the developed model. Some important simulation results were discussed, including mass loss rate, top and bottom surface temperature, temperature distribution in solid. The capability of the model was verified by the comparison between experimental and simulation results. Results showed that some detailed behaviors of the thermal degradation were significantly affected by the absorption modes, like temperature in solid, top surface temperature and initiation of pyrolysis etc. Both hypotheses were acceptable within predicting bench scale experiments.