Numerical simulation of radiation intensity of a long-endurance UAV exhaust system with 2D nozzle

Exhaust system is the most important infrared radiation source of a long-endurance UAV and the shape of the nozzle contribute to the infrared radiation characteristics of exhaust system. This paper built a 2-D nozzle and use ANSYS14.5 simulated the temperature filed of the plume. And then, spectral infrared radiation characteristics of the plume were obtained by the single band C-G approximation method. Finally, the infrared radiation intensity distribution of the exhaust system of the 2-D nozzle in different planes is obtained. The results show: The infrared radiation of the plume in wide side detection surface is far greater than the narrow side; The infrared radiation of the nozzle in wide side detection surface is smaller than the narrow side; The infrared radiation of the exhaust system in wide side detection surface is smaller than the narrow side. The results maybe contribute to the further study of the infrared radiation characteristics of the long-endurance UAV.