The mixing process of pre-evaporated afterburner fuel at different positions upstream of the mixers and airflow was numerically simulated in a straight channel, with semicircular mixer, rectangular mixer, triangular mixer and chevron mixer respectively. The effects of vortices generated by mixers on fuel distribution and mixing characteristics were studied. The results show that: (1) The scale, strength and breaking speed of the streamwise vortex and the development speed of normal vortex are different downstream of the four mixers, which accelerate the mixing process of fuel and airflow. (2) The fuel distribution at the outlet of mixers, downstream of straight section and downstream of the crest and trough is mainly affected by secondary flow, the streamwise vortex and the normal vortex respectively. (3) The fuel mixing uniformity downstream of the four mixers is increased by about 80% compared with no mixer. In the limited distance, the mixing performance of chevron mixer is the best, while the triangular mixer is the worst Rectangular mixer has the fastest mixing speed and superior comprehensive performance. In addition, the effect of the channel wall on the mixing process downstream of mixers cannot be ignored.
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