抄録
The time averaged, steady, flow in a sudden contraction flow passage has two distinguished clockwise vortices which appear just before and after the contraction. The latter vortex makes decrease the effective cross sectional area passing through the flow and increase the flow resistance. But, in practice, vortex is shed one by one periodically from the edge of the contraction. In this study, the mean and vortex shedding flow characteristics are examined and a simple method to control and suppress the arising vortex just after the contraction is shown.
