Investigation of hot-jet characteristics of 2-D C-D vectoring nozzles

A new propulsion concept of 2 D C D vectoring nozzle was proposed, which had a convergent duct shaped by spheric surface and a divergent one with rectangular transverse section. The nozzle models were designed at 3.3 nozzle pressure ratio and had several fixed vectoring angles such as 0 °, 10 °, 20 °. On little setup of generating high temperature exhausts, some experiments have been carried out on the aerodynamic performance and jet structure of the nozzle models on the conditions of the temperature 823K at the nozzle inlet and the nozzle pressure ratios such as 1.46 and 2.25. The static pressure along the center lines and the total pressure at exit of the model nozzles were tested by the use of pressure probe, and the corresponding jet structures, including the shock wave changes in shape downstream, were observed from different view angles with IR thermal image instrument. The results show that flowing separation certainly occurs inside the divergent duct and yields serious distortion in total pressure at nozzle exit at nozzle overexpanded state. Especially in the corresponding jet field, there are two streams of smaller jet potential core embedded with a series of different shock waves in shape and IR signature.