In all commercial and non-commercial airplanes, there is no fire detection or fire extinguishing system in theudavionics bay. Racks, are cooled by ambient or conditioned air. Each rack will include several circuit boards, whichudin case of overheat, can burn with the risk of igniting the surrounding components and structures, thus jeopardizingudflight safety. It becomes therefore important to provide fire detection and fire extinguishing capabilities in the aircraftudavionics compartment. The approach proposed in this paper, extracts nitrogen from ambient air by mean of the AirudSeparator Module, then nitrogen is routed to the avionics compartment racks, and enters inside the component andudextinguishes the fire. The temperature of the nitrogen is adjusted to be around 25°C to prevent thermal shock effectsudon the circuit boards before being injected in the avionics compartment. A series of experiments conducted, aimedudat gathering information by using dry nitrogen under different pressure values to extinguish different size of fire. Theudanalysis of the experiment research showed that increasing nitrogen pressure, resulted in quicker extinguishing time.udThis is because nitrogen under higher pressure, quickly decrease the oxygen concentration in the air for the fireudalready in the process of combustion. Nitrogen does not conduct electricity thus cause no short circuits during andudafter the extinguishing process, therefore, they are ideal for use in the electronic systems.
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