II.2. A flow structure at reattachment region of a two-dimensional backward-facing step by using advanced multi-point LDV

摘要

A temporal data of instantaneous velocity profile of a two-dimensional backward-facing step flow was measured by multi-point LDV, and was discussed with a special focus on the details fo the separated shear layer and the phenomena of reattachment. As a result, The phenomenon of reattachment was seen to follow two patterns, one when the separated shear layer reattaches, the other when the separated shear vortex reattaches. The dividing stream line oscillates because of vortex concentration in the separated shear layer and has a quasiperiodical behavior as concerned to reattachment.