Low-temperature refrigeration nitrogen-making oil tank inerting system and working method thereof

Abstract

The invention discloses a low-temperature refrigeration nitrogen-making oil tank inerting system and a working method thereof, and belongs to the technical field of fire prevention and explosion prevention. The working method comprises the following steps: air is entrained from an aircraft engine, goes through a filtering device, a heat exchanging device and a water removing device, and then is condensed into liquid air by an onboard refrigerating device, and the liquid air is separated in a rectifying tower to form a nitrogen-rich liquid and an oxygen-rich liquid. The stored nitrogen-rich liquid can be used for aircraft fuel tank inerting through the pressure reduction effect, so the oil tank combustibility is reduced, and aircraft flight safety is protected; and the oxygen-rich liquid can be used for supplying oxygen to an aircraft cockpit after being decompressed. The oil tank inerting system can store nitrogen-rich gas, reduce the influence on engine bleed air, meet the requirementfor aircraft oil tank inerting under full flight envelope and extreme conditions, and can be used for supplying oxygen when a cabin loses pressure to guarantee flight safety.

Description

technical field [0001] The invention relates to the technical field of fire prevention and explosion protection, and relates to an inerting system for a low-temperature refrigeration nitrogen production tank and a working method thereof. Background technique [0002] When the oxygen concentration in the gas phase space of the aircraft fuel tank is greater than the minimum flammable limit oxygen concentration, and when there is an external ignition source, the fuel tank is extremely prone to combustion and explosion, resulting in aircraft crash and death. Fuel tank inerting technology is an efficient and economical method to reduce the flammability of fuel tanks and reduce the occurrence of fires. It uses inert gases such as nitrogen or carbon dioxide to fill the gas phase space of the fuel tank to replace the oxygen in it, making it lower than the fuel required for combustion. The lowest flammable limit oxygen concentration, to achieve the purpose of inerting the fuel tank. ...

AI Technical Summary

Problems solved by technology

However, with the deepening of the research on fuel tank inerting technology, more and more problems have been exposed in the hollow fiber membrane nitrogen inerting technology, such as the high bleed air pressure required, which will not affect the engine performance; Short service life leads to increased maintenance costs; and during the descent phase of the aircraft, due to the increase in external pressure, a large amount of air enters the fuel tank, resulting in a rapid increase in oxygen concentration, resulting in the hollow fiber membrane nitrogen inerting system failing to meet the inerting requirements

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