Influence of afterburning on infrared signature of rocket motor exhaust plume

To study the infrared signature of rocket motor afterburning exhaust plume, the calculation model for infrared radiation(IR) transfer of rocket motor was built. The radiation source item was induced to energy equation, and the plume flow field and radiation transfer was calculated together. Finite rate chemistry reaction model was used to simulate 10 species afterburning exhaust plume; finite volume method and discrete ordinates method were separately used to solve the plume flow field and the radiation transfer equation. The spectral radiation intensity from 1 μm to 15 μm and radiation intensity contours were obtained, both of which agreed well with the experimental data from articles. The results show that the IR characteristics in the near plume field can be captured dependently from the physical characteristics of flow field, indicating that the coupled solution can increase the calculation resolution. With the increase of Mach number and flight height, the radiation intensity increment of exhaust plume caused by afterburning effect declines.