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Prediction of the Rear Fuselage Temperature with Radiation Shield

� Abstract—In order to enhance the aircraft survivability, the infrared signatures emitted by hot engine parts should be determined exactly. For its reduction it is necessary for the rear fuselage temperature to be decreased. In this study, numerical modeling of flow fields and heat transfer characteristics of an aircraft nozzle is performed and its temperature distribution along each component wall is predicted. The radiation shield is expected to reduce the skin temperature of rear fuselage. The effect of material characteristic of radiation shield on the heat transfer is also investigated. Through this numerical analysis, design parameters related to the susceptibility of aircraft are examined. Keywords—Infrared signature, Nozzle flow, Radiation shield, Rear fuselage temperature, Susceptibility I. INTRODUCTION URVIVABILITY of aircraft has been a one of the important factors in modern battlefield in which the standard of technology determines the supremacy. Military forces are engaged in equipping a stealth function to the fighter plane at the early stage of design. The importance of susceptibility problem has been strengthened related to detection and tracking by enemy missiles or seekers. It is well known that aircraft survivability is threatened by detection using radar and thermal infrared(IR) sensor as well as by primary ways such as visual and sound sources. Several varieties of detection systems have been developed and their technology has been more sensitive, therefore signature reduction technology is excessively in need of development. Advanced countries lead the survivability and susceptibility research (1, 2), but they strongly control the outflow of these technologies overseas. High level of infrared signature emitted by aircraft rear fuselage is an easy target for IR detectors, therefore reduction of IR signature is essential for the improvement of survivability. IR signature can be predicted by figuring out the distribution of the rear fuselage temperature, because IR signature is a function of temperature. The numerical analysis of nozzle flow needs to be preceded to estimate the skin temperature precisely,