Numerical Simulation of Spontaneous Ignition in Rubber Woodchip

This study used numerical analysis to examine the spontaneous ignition of rubber woodchip in a cube basket within a convection oven. The study used a bulk of cubic rubber woodchip as an open container that let oxygen from the surrounding air in and interacted with the fuel. The self-ignition temperature was simulated using COMSOL Multiphysics and coupled partial differential equations for conductive and diffusive heat transfer. After then, the outcomes of the experiments and the simulations were compared. The observed and simulated center temperatures of the cubic rubber woodchip basket generally agreed well. With an increase in cubic sample size, the time to self-ignition increased as well. In comparison to the experiment results, the self-ignition temperatures estimated by 2D modeling varied by 11 °C.