Experimental study on the effect of sloping substrate on the spill fire in a well-confined ship engine room

Fuel leakage in the ship engine room tends to form the dynamically evolving spill fires instead of pool fires, which are full of danger and have been scarcely concerned. In this work, one-dimensional spill fire experiments with different fuel leakage rates and substrate slopes are tentatively conducted in a well-confined model-scale ship engine room to reveal their fire dynamics characteristics. It is found that the development of spill fires in the ship engine room is quite different from that in open space, and it, to a great extent, depends on the specific leakage rate and substrate slope. Typically, the spill fire in the ship engine room can be divided into five stages: continuous spreading, steady burning, burning shrinkage, quasi-steady burning, and decay stages, while the steady or quasi-steady stage does not always appear for all cases. In the quasi-steady burning stage, the thickness of the critical oil film is between 0.97 and 1.55 mm, smaller than that in the open space. The special fire phenomena are mainly attributed to the confined boundary condition, where the competing mechanisms of fuel control and ventilation control effects will collectively influence the development of the spill fire in the ship engine room. Characteristic parameters of spill fires in ship engine room, including flame spread rate, burning area, burning rate, and flame height, are also quantitatively analyzed.