Numerical investigations on combustion characteristics of full-size cabin fire with typical material pyrolysis and burnout under different fire source positions

Abstract

This study primarily investigates the combustion characteristics of full-scale cabin fires under different fire source positions based on the pyrolysis and burnout of the typical cabin combustibles. The flame spread, mass loss rate (MLR), heat release rate (HRR), smoke movement characteristics and temperature decay were analyzed. Results showed that the cabin flame spread under different fire source positions could be divided into four stages. The fire source position significantly influenced the growth rate of MLR and HRR, but had little effect on the peak value. Comparison of the theoretical HRR based on fuel and ventilation control with the simulation data verified the dynamic change of cabin fire. The confined space and continuous intense combustion made the smoke movement driven by weak and strong plume in cabin fire. The fire source position had the great influence on TBL in the initial stage of cabin fire. The temperature decay correlation ln(ΔTmax(abs(x−a)/L)ΔTmax)∝C(abs(x−a)/L) considering the flame spread was proposed, which was well consistent with the simulation results. The conclusions would be helpful to understand the cabin fire and provide the theoretical reference for evacuation.