论文部分内容阅读
随着红外探测和红外制导技术的迅猛发展,飞行器的生存力受到越来越大的威胁,如何降低飞行器的红外辐射特征成为提高隐身能力的关键技术之一,排气系统是飞行器后半球的主要红外辐射源。为了研究飞行器后机身蒙皮的红外辐射特性,针对飞行器的后机身蒙皮,结合涡扇发动机引射喷管的CFD计算,采用离散传递法计算了典型作战飞行器在8～14μm波段的红外辐射强度分布。在红外计算过程中,考虑了发动机固体壁面的发射和反射,飞机蒙皮的发射,燃气内CO2、H2O和CO的吸收与发射作用;并通过冷却、隔热等措施降低后机身发动机热影响区蒙皮的温度对红外辐射特征的影响进行了研究。计算结果表明:后机身发动机热影响区温度降低70 K,在红外探测的主要威胁方位头向5°范围内可以降低整机红外辐射强度9.1%,30°可以降低15.4%,60°可以降低17.5%,在正下方90°,可以降低18.9%;在此基础上采用低反射率可以在各个方向上进一步降低飞机的红外辐射强度,除了正后向及附近排气系统喷管腔体影响强烈扇区间以外,都能降低到20%以内。计算结果和方法为飞行器红外隐身设计提供了有益参考。
With the rapid development of infrared detection and infrared guidance technology, the survivability of aircraft has been increasingly threatened. How to reduce the infrared radiation characteristics of aircraft has become one of the key technologies to improve stealth capability. The exhaust system is the main part of the aircraft’s rear hemisphere Infrared radiation source. In order to study the infrared radiation characteristics of the fuselage skin after the aircraft, aiming at the fuselage skin of the aircraft and the CFD calculation of the jet nozzle of the turbofan engine, the discrete transmitting method is used to calculate the infrared radiation of a typical combat aircraft in the 8-14 μm band Radiation intensity distribution. In the process of infrared calculation, the emission and reflection of the solid wall of the engine, the emission of the skin of the aircraft, the absorption and emission of CO2, H2O and CO in the gas are considered, and the thermal influence on the rear fuselage engine is reduced through measures such as cooling and heat insulation The influence of zone skin temperature on infrared radiation characteristics was studied. The calculation results show that the temperature of the heat-affected zone of the rear fuselage is reduced by 70 K, and the infrared radiation intensity of the whole machine can be reduced by 9.1%, 15.4% at 30 ° and 60 ° at the head of the infrared detection ranging from 5 ° to 5 ° 17.5% at the bottom, 90% below which can be reduced by 18.9%; on the basis of this, the use of low reflectivity can further reduce the infrared radiation intensity of the aircraft in all directions, except for the positive rearward and nearby exhaust system nozzle cavity Outside the sector, can be reduced to less than 20%. The calculation results and methods provide a useful reference for the infrared stealth design of the aircraft.