Numerical and experimental study on flame spread over conveyor belts in a large-scale tunnel

• A CFD model was developed to simulate flame spread over conveyor belts in a tunnel.
• TGA analysis was used to estimate the belt kinetic properties of pyrolysis process.
• The CFD model was calibrated based on large-scale experimental results.
• The calibrated CFD model captures major characteristics of the flame spread over belt.
• The model can characterize conveyor belt fire hazard under different conditions.

Conveyor belt fires in an underground mine pose a serious life threat to the miners. This paper presents numerical and experimental results characterizing a conveyor belt fire in a large-scale tunnel. A computational fluid dynamics (CFD) model was developed to simulate the flame spread over the conveyor belt in a mine entry. Thermogravimetric analysis (TGA) tests were conducted for the conveyor belt and results were used to estimate the kinetic properties for modeling the pyrolysis process of the conveyor belt burning. The CFD model was calibrated using results from the large-scale conveyor belt fire experiments. The comparison between simulation and test results shows that the CFD model is able to capture the major features of the flame spread over the conveyor belt. The predicted maximum heat release rate, and maximum smoke temperature are in good agreement with the large-scale tunnel fire test results. The calibrated CFD model can be used to predict the flame spread over a conveyor belt in a mine entry under different physical conditions and ventilation parameters to aid in the design of improved fire detection and suppression systems, mine rescue, and mine emergency planning.