Performance of overall heat transfer coefficient and exploring heat transfer through the ceiling vent of compartment fire in ship structures with A60 constructions

Exploratory investigations on overall heat transfer coefficient of compartment fires in ship structures with A60 constructions were conducted, as well as heat transfer through ceiling vented compartments in such constructions. The results indicated that the overall heat transfer coefficient decreased with the burning process, as well as the cooling process after the extinction. From the view of temperature difference, the overall heat transfer coefficient decreased exponentially with the rising temperature difference for “temperature rise” stage, and increased linearly with the increase of the temperature difference for “temperature drop” stage. For the tested cabin, the average overall heat transfer coefficient was in proportion to one-third power of the heat release rate. In addition, care should be taken in applying Cooper algorithm to calculate the mass flow out of the ceiling vented compartment for fires directly beneath the ceiling vent, under which the plume-induced flow may be the dominant factor under such circumstance. Finally, a potential method was suggested to deal with the ceiling vent flow for fires positioned directly under the ceiling vent.