Fire development and smoke propagation in ship compartments: Fid-Bau Portal

Fire development and smoke propagation in ship compartments

Shigunov, V.

The calculation method presented can provide results of acceptable accuracy for fire safety assessment with small computing time requirements. This is a large advantage, because it is difficult to accurately scale results from model tests and large-scale experiments are very expensive and involve many practical problems. The method would be especially useful when combined with evacuation simulation. Nevertheless, the basic idea of using very coarse grids does not allow to study flows with strong influence of diffusion or mixing, where much finer grids must be used. This is especially important in multiphase applications for fire damping systems. At the present level of approximation, there remain same quest ions for further exploration, e.g. whether the simulation of the normal heat conduction through walls is enough for ship design applications or if longitudinal heat conduction must also be included. For high compartments such as staircases, the assumption of uniform density of the lower gas layer, neglecting the stratification due to the gravity, may lead to wrong results if the buoyancy of the combustion products is not enough to reach the ceiling and the hot gas layer forms at an intermediate height. For such applications, more than two gas layers must be considered. For rooms with large horizontal dimensions like cargo decks and corridors, the assumption of uniform thickness of the hot gas layer overestimates the speed of propagation of heat and combustion products from fire. The problem can be solved by further horizontal subdivision of such compartments into smaller, but still large control volumes, which needs the incorporation of momentum transport into the model.