Abstract
During typical supersonic cruising, the temperature of the aircraft skin rises above 300 K due to aerodynamic heating. In this situation, aircraft-skin infrared (IR) suppression, used to minimize the radiation contrast from the background is a crucial survival technology. In the present study, a technique to evaluate the effectiveness of IR suppression of aircraft skin is proposed. For this purpose, a synthetic procedure based on numerical simulations has been developed. In this procedure, the thermal status of aircraft skin is obtained using a computational fluid dynamics (CFD) method for complex aircraft geometries. An IR signature model is proposed using a reverse Monte Carlo (RMC) technique. The detection range and the IR contrast are adopted as the performance indicators for the evaluation of the aircraft IR suppression. The influence of these factors related to the aircraft-skin radiation, such as aircraft-skin emissivity, surface temperature distribution and flight speed, on the IR contrast and the detection range is also studied. As a test case, the effectiveness of various IR suppression schemes was analyzed for a typical air combat situation. Then, the method is applied to clarify the contribution of each aircraft component to the IR suppression of the overall IR radiation. The results show that aircraft-skin temperature control and emissivity control are effective means to reduce the IR radiation and to achieve lower detection. The results can be used as a practical guide for designing future stealth aircraft.
