Abstract
This paper describes the model experiment and its numerical simulation for the vortex structure between a main flow and a backflow at the turbomachine inlet at a low flow coefficient. In the model experiments, the vortex structures were visualized by the injected air and recorded by a high speed video for various flow ratios of the axial and tangential speeds of the backflow to the axial speeds of the main flow. The numerical simulations are performed for some experimental conditions and the results agree with the experimental ones qualitatively. All the results show that the ratios of the axial and tangential speeds of the backflow to the axial speeds of the main flow greatly influence on the number of vortices.
