Theoretical and experimental investigation of fires in large fuel tanks and creation of an innovative technology of their extinguishment

Fundamental inefficiency of existing foam fire systems extinguishing tanks with oil and petroleum products having a volume of 5000 m$^{3}$ or more is shown by methods of mathematical modeling. The required foam supply intensity and foam supply rate allowing effective fire suppression in large tanks with a volume of up to 20000 m$^{3}$ are theoretically predicted. On this basis of theoretical conclusions, a new method of foam fire extinguishing in large fuel tanks has been developed. To obtain the required intensities and supply rates, fire extinguishing foam is formed in a special container with the use of solid-fuel gas generators. The theoretical predictions were confirmed in 21 full-scale successful experiments, in which fire suppresion system based on the new method was able to extinguish a fully developed gasoline fire in tanks with a volume of 5000 m$^{3}$ and 20 000 m$^{3}$ just for 30-90 seconds. The required amount of the foaming agent to extinguish a fire in a 20 000 m$^{3}$ tank is only 450 liters, which is at least 100 times less than for traditional foam fire fighting Contribution of the authors: the authors contributed equally to this article. The authors declare no conflicts of interests.