Experimental study on combustion behaviors of thin-layer methanol with lateral continuous leakage

Abstract

Fire accidents caused by liquid fuel leaks occur at times. In this paper, the combustion behavior of thin layers formed by the free spread of methanol at six continuous leakage rates was studied. The results show that methanol combustion with continuous leakage can be divided into four stages according to the change of burning area. The quasi-steady burning rate of thin-layer fuel is lower than that of pool fire at the same scale, due to the rapid heat exchange between the fuel layer and the substrate. As measured and calculated, the average fuel layer thickness gradually decreases in the spread burning stage, rises in the shrink burning stage, and finally reaches stability. The average fuel layer thickness of the quasi-steady burning stage of each case is used to calculate the heat loss by substrate reflection. Based on the law of energy conservation, a heat equilibrium model of the quasi-steady burning stage of a thin layer combined with fuel flow heat transfer was established. This model explains the uneven substrate temperature found by experimental measurements. The calculation results show that the effect of flow heat transfer is more significant within 20% of the burning area near the leakage port.