In order to reduce the infrared radiation of aircraft

and make the exhaust system match the aircraft afterbody

a kind of unconventional two-dimensional(2-D)S-nozzle was designed to suppress the infrared radiation characteristics. There was a small offset given that the nozzle's center line and the engine's axis were not collinear. Based on the distribution of temperature

pressure and species mass fraction of the two-dimensional S-nozzle obtained from CFD results

the infrared radiation characteristics of two-dimensional S-nozzle was calculated with reverse Monte-Carlo method

then analyzed and compared with axisymmetric nozzle. The results show that

the two-dimensional S-nozzle is capable of shielding the high temperature elements inside the exhaust system effectively

and the infrared radiation characteristics of the exhaust system can be further suppressed by 33%.