| Boilover accidents often take place in an aquiferous oil tank in the process of production and storage. When boilover happens, the heat radiation increases strongly, meanwhile, after quite a long period of burning sprayed oil could affect adjacent oil tanks which will lead to a second hazard, so boilover fire is considered as one of the most severe accidents of tank fire for its special combustion aspects. Therefore, once boilover happens in an oil storage tank, people's lives and state's property will suffer a heavy loss. However, because boilover phenomena are very complex including several fundamental physi?aw people in time. In this paper the research for this topic is conducted as follows.From the results of a careful analysis of the whole boilover phenomenon, a typical boilover process could be empirically divided into three basic stages, i.e. a quasi-steady period, premonitory period and boilover period. Hence, understanding the mechanism of the premonitory phenomena correctly is the first step to understand the occurrence of boilover. In this paper a series of small-scale simulation experiments of boilover in the tank fire are carried out, based on theoretic analysis and mathematical deduction, the forming mechanism of hot zone and the occurrence condition of boilover are studied particularly, the effects such as oil depth and water contents of different oil on boilover fire are also discussed.The rule of heat wave spread is analyzed in details. On the basis of heat balance of tank fire, the calculating formula of hot layer temperature is deduced. By analyzing the characteristics of heat transfer in the oil/water interface, disposing experimental data by mathematical software, a model for predicting the time to the onset of boilover in tank fire is founded and the error of this model is also discussed.Numerical simulation of boilover in the tank fire is studied. As boilover fire is a violent burning of flammable organic substances in the open environment, according...
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