Simulation Study On Fire Temperature And Flue Gas Law In Enclosed Cabin Of Ships

The rapid development of the economy has stimulated the prosperity of the water transport industry.In recent years,the number of new vessels put into operation has been constantly increasing.The scale of the vessel has also been expanding.As a result,there have been more and more ship fires and serious fire consequences.In particular,A series of complicated problems arising from the closed-chamber fire have become prominent day by day.Therefore,it is necessary to study the temperature and flue gas law of the closed-vessel fire in the ship.In this paper,a small-scale closed-tank model was developed to study the temperature distribution of fire in the confined space,the law of flue gas flow and the characteristics of combustion.The experimental model is a closed cabin cube with an inner dimension of 1000 mm in length and width,respectively,to study the combustion characteristics of the fire in a closed state.The experimental data are analyzed by theoretical analysis and dimensionless rules.The study of the temperature distribution and the movement law of flue gas in the combustion chamber is mainly studied.Mainly includes the following contents:First of all,the closed cabin fire,the temperature has gone through three stages,namely the fire development stage,the fire stable rise stage and the flameout cooling stage.The temperature change in the development stage and the stabilization phase of the fire stage is similar to that of the above-ground building space.The temperature distribution in the extinguishing stage is a segmented function.The temperature of the flameout time is analyzed by establishing a function model to provide the choice of re-opening time for fire fighting in the ship's fire the theoretical basis.Secondly,the temperature of the closed fire in the vertical direction,the compartment temperature is divided into the upper high temperature zone and the lower uniform gradient area,the high temperature zone has the same temperature,the uniform gradient region temperature is a high degree of the first function,linear growth relationship;in the horizontal direction,The same level of altitude in the cabin space has a similar temperature value.The closed-tank fire smoke in the stable combustion period and the ground building space fire there is a big difference,will continue to produce the phenomenon of recirculation,and ultimately the formation of a dynamic balance of the upper and lower flue gas until the oxygen in the closed compartment is consumed So extinguished.Finally,the closed-tank fire smoke is divided into two periods,namely,the beginning of the fire and the stable burning period.At the beginning,the flue gas in a relatively short period of time to fill the entire space,the chamber from the bottom down can be divided into cold air layer,transition layer and hot smoke layer;stable period,the cold air layer was smoke and squeeze,The cabin only the lower part of the smoke layer and the upper part of the smoke layer.Ship fire,because the flue gas has a certain dimming effect,resulting in low visibility of smoke occasions,very detrimental to the personnel in the fire for safe evacuation.Therefore,through the study of the temperature distribution and the law of flue gas in confined space fire,it has the reference value and basis for practical operation of ship fire rescue and fire fighting.