Abstract
This paper describes the model experiment 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. Number of vortices are greatly influenced by the ratios of then axial and tangential speeds of the backflow to the axial speeds of the main flow.
