Numerical investigation was performed to study the aerodynamic and infrared performances of spherical convergent two-dimensional vectoring nozzle adopted in turbofan engine exhaust system

only the ground status simulation and pitch deflection were taken into consideration. Results showed that

the pitch deflection had a very weak impact on the thrust coefficient and total pressure recovery coefficient of exhaust system when the pitch deflection angle was less than 20 degree. The aerodynamic thrust vectoring angle was nearly the same as the pitch deflection angle. Due to the feature of volumetric thermal radiation of gas

the variation of nozzle pitch deflection angle resulted in significant change of infrared radiation directionality of hot plume. The infrared radiation of hot plume in 3-5μm band was also increased within a certain scope in relation to the no-vectoring case. With respect to the total infrared radiation of exhaust system in 3-5μm band

the peak infrared radiation intensity decreased as the pitch deflection angle increased. The detecting angle corresponding to the peak infrared radiation intensity was smaller than the pitch deflection angle. Under a big pitch deflection angle

the total infrared radiation of exhaust system viewed from top in the vertical plane was lower than that of no-vectoring case. However

the total infrared radiation of exhaust system viewed from bottom in the vertical plane was higher than that of no-vectoring case

resulting in a secondary peak value.