The Simulation and Validation of Smoldering in a Burning Cave

Abstract

Abstract. In this study, simulations of forward and opposed smoldering in a burning cave were carried out by computational fluid dynamics (CFD) modeling. The fuel in the burning cave was considered a multiphase porous medium with uniform heating. The heat release rates for forward and opposed smoldering in the burning cave were also calculated with an inverse method based on the CFD model. Experiments were conducted to validate the accuracy of the simulation model and the heating performance of the burning cave. The results showed that the model accurately predicted the temperature distributions in the burning cave with an error of 5% to 10% compared to the experimental results. Calculations showed that the heat release rate was 850 W m-3 for forward smoldering and 500 W m-3 for opposed smoldering with an air inlet velocity of 0.1 m s-1. When the air inlet velocity was increased to 0.3 m s-1, the heat release rate increased from 850 to 2,000 W m-3 for forward smoldering and from 500 to 1,000 W m-3 for opposed smoldering. Forward smoldering produced rapid heating in the burning cave but caused uneven temperature distribution on the roof. Conversely, opposed smoldering heated the burning cave at a slower rate, but the temperature distribution on the roof was uniform. Keywords: Burning cave, CFD simulation, Multiphase porous media, Smoldering.