Integrated Research And Analysis On Anti-Explosion Of Civil Aircraft Fuel Tank

Since1959,17aircraft fuel tank burning accidents happened in the world, which leads to542people’s death and11aircrafts’ lose. A series of accidents have proved that the blast accident ofaircraft fuel tank is one of the key factors that have effect on the safety of aircraft. As an importantguarantee for safe operation of the aircraft, fuel tank needs to store fuel and adjust the center ofgravity of aircraft. In the aircraft fuel tank, there are combustible material (which is aviation kerosenevapor)，oxygen and all kinds of potential fire sources which can cause combustion or explosion thatseriously threaten the safety of the aircraft.This paper synthetically analyzed the flammability and security of the fuel tank on the basis ofthe fire triangle and the flashpoint, the vapor pressure and flammability limit of the kerosene vapor,the oxygen concentration distribution in different flight condition and the potential ignition sourcewithin the aircraft fuel tank.Then, the formation and propagation law of the gas explosion shock wave were analyzed basedon the basic knowledge of gas explosion theory. The detonation temperature, detonation velocity,detonation pressure, detonation heat and initial internal energy of the gas mixture w ere calculatedunder three conditions of volume ratio.At last, the finite element model of fuel tank was established based on ANSYS/LS-DYNA, theload curve which act on the fuel tank was confirmed through pertinent literature and the parameters ofgas explosion. The characteristic of deformation and equivalent stress on the fuel tank were as follows:when the fuel tank under explosion load, deformation is different in each part of the fuel tank, the fueltank part which is in the range of elastic deformation will get a certain amount of recovery; theequivalent stress on arris and vertex of the fuel tank is larger than other parts of the fuel tank, theintensity of arris and vertex should be enhanced during design phase.