Research On Physicochemical Characteristics&Flammability Of Domestic Fuels

The fire and explosion suppression in aircraft fuel system is one of the hot issues today, becauseof its important effect on survivability and vulnerability of aircraft as well as the fighting intensity,cost of plane, safety of passengers. Nowadays, the main methods for the explosion suppression inaircraft tanks are to restrain the formation of inflammable mixture in ullage of tank and prevent theemerging from ignition sources.Basically, it is almost impossible to definitely prevent the formation of inflammable mixture andmake an accurate assessment of ignitibility in the tank if without the fundamental physicochemicalproperties and flammability of the fuel. Current research attributions on the fuel flammability basedon JET A and JP-4fuels cannot be directly employed to assess the flammability of the domestic fuelsand to design the fuel tank inerting system due to the difference of the physicochemical properties.Consequently, the following works have been conducted based on RP-3fuel:1. The chemical composition, hydrogen weight ratio and hydrocarbon composition weight ratioof the domestic RP-3fuel are experimentally obtained and the average molecular formula is acquired.These could be helpful to calculate physical-chemical properties of the RP-3fuel. Furthermore, theflammable limit and influence factors are discussed.2. The method to calculate the bursting limits was systematically summarized, then it wascalculated based on the chemical composition and physicochemical properties. Finally, thecombustible limit diagram of RP-3fuel was drawn to determine the minimal oxygen concentration.3. An case was presented based on a domestic plane XX. The calculating model to obtain the fueltemperature in flight envelope was set up. The solved results reveals high agreement with the testdata.