Modeling and Analysis of Helicopter Thermal and Infrared Radiation

The temperature distributions on the helicopter airframe and in the exhaust plume are affected seriously by the engine exhaust system, rotor downwash and solar irradiance. To precisely simulate temperature distribution on the helicopter airframe and in the exhaust plume, the effects of rotor downwash and solar irradiance are considered in three-dimensional flow and heat transfer calculation under helicopter hovering. Based on the temperature distribution, a forward-backward ray tracing method is used to calculate the helicopter infrared (IR) radiation intensity. A numerical study is conducted on a fictitious helicopter model with an integrated exhaust system-tail airframe configuration, and the thermal and infrared radiation characteristics are analyzed.