Study Of The Influence On Cooling Effect To Combustion Characteristics Of Oil Tank Fire

As the consumption and storage of large quantities of petroleum and its products, the resulting potential risk of accidents has gradually increased. And if an accident occurs, it will cause huge losses, so studying combustion characteristics of oil tank fire, and exploring the prevention and control method of tank fires are very important. In the article, fire control method after tank-fire was focused on, and the cooling coil inside the tank, the tank wall cooling and other cooling solutions by experiment were studied. Variation of heat release rate and other parameters before and after the cooling were analyzed, and the simulated results were compared with the experimental results.The feasibility of cooling control tank fire was analyzed in the article, and the theoretical formula about the characteristic parameters was evaluated.Variation of heat release rate and other parameters without the cooling was studied and analyzed. It showed that the combustion characteristics of tank fire were closely related to tank diameter, tank level, and the opening. Larger diameter tank, the higher the level, the greater tank-port, the bigger the heat release rate. The cooling effect of cooling inside the tank was studied. The result showed that at low level, the internal cooling effect of controlling fire was good, at high level, the cooling effect was not obvious, characteristic parameters changed little. After the improvement of the internal cooling system, fire control effect was improved obviously at this time, at middle-level, heat release rate was reduced by 40%, burning time extended the half. Combustion characteristics of external tank wall cooling were studied. The effect of external tank wall cooling was related to water consumption per surface area of tank wall. Studies showed that even with very little water, it can also reach the cooling effect inside the tank, more economical compared to other cooling methods.Hindering effect resulting from obstacles was studied. The presence of obstacles can greatly influence the spread of flames, thereby affecting the heat release rate, thermal radiation, flame height and other parameters. In the paper, analysis was made about the flame shape, the flame height and fire parameters in the same time. It showed that various parameters in the stable stage agreeed well with outside flame characteristics. In this paper, the heat release rate of tank fire, flame temperature distribution and heat distribution were simulated by pyrosim and compared with experimental results, the results showed that the numerical simulation for predicting the thermal radiation field, the flame temperature agreeed with the experimental value well, less than 10%. But numerical of heat release rate was smaller. Generally numerical simulation can provide powerful tool for predicting the combustion characteristics of larger tank and oil tank fire design.