IR characteristics of aircraft aft fuselage skin

The rapid development of infrared detection and infrared guidance technology poses more threat to the survival ability of aircraft. How to reduce the infrared radiation of the aircraft becomes one of the key technologies to improve the ability of stealth. The exhaust system of aircraft is the main source of infrared radiation. In order to study the IR characteristics of the aft fuselage skin, based on the discrete transfer method in the paper, the infrared simulation of the aft fuselage skin for a typical fight aircraft was carried out to analyze the infrared radiation intensity distribution of the aft fuselage skin for a typical combat aircraft with the ejector nozzle in 8-14 m band by the form of a combination of the computational fluid dynamics(CFD) commercial software and self-developed IR computing software. In the IR calculations, the emission and reflection of the solid wall of the engine, aircraft skin launch, gas, CO2, H2O and CO absorption and emission effects were taken into account. Finally, the IR intensity of the fighter were investigated using the cooling insulation way and low infrared emissive material. It was found that the temperature of the engine heat-affected zone of the aft fuselage of the fighter were reduced by 70 K, the IR intensity of aircraft declined by 9.1%, 15.4% and 17.5% in the infrared detecting main threat orientation of the head within 5, 30 and 60, and reduced by 18.9% in just below 90. The skin of the engine heat-affected zone were covered by low emissive material, the IR could be reduced by 20% in the font basis. The results of research in this paper are of considerable guiding significance and referential importance for designing infrared stealthy aircraft.