Experimental and numerical simulation study of typical semi-transparent material pyrolysis with in-depth radiation based on micro and bench scales

Abstract

With the increasing use of semi-transparent material such as photovoltaic panel and PMMA in our modern life, their cyclic utilization has been paid more attention. Pyrolysis, as the key step for thermal conversion, is studied in our current study. Multiple-scale pyrolysis experiments including micro-scale thermogravimetric experiment and bench-scale fire propagation apparatus experiment are conducted. The numerical simulation is carried out on a modified version of FireFOAM within the OpenFOAM toolbox and the predicted results agree well with experimental data, especially basically reproduce the main pyrolysis temperature range and the highest mass loss rate. By coupling of experiment and numerical simulation, the connection of multiple scales is achieved. Namely, the chemical reaction kinetic parameters are obtained from micro-scale thermogravimetric experiment and then set as simulation input parameters. Bench-scale fire propagation apparatus experiment is used to provide simulation validation data when both chemical reaction kinetics and physical mass/heat transfer are considered. Moreover, in view of the non-negligible transmission of light for semi-transparent material, the in-depth radiation is supplemented in our current simulation and the eventual simulation results further prove its important effect on the pyrolysis, especially the maximum of pyrolysis mass loss rate, pyrolysis duration time, top surface and inside temperature.