微細気泡をトレーサとした PIV 計測の検討

抄録

The purpose of this examination is evaluate usefulness of microbubble for PIV. It is necessary to compare microbubble and solid particle because specific gravity of them are different. Mean diameter of microbubbles are around 40μm. Investigations has been done using backward-facing step flow (Re=11000). The channel has an aspect ratio of 6 and expansion ratio is 2. This investigations show distribution of mean velocity and Reynolds stress. The result using microbubbles generally consisted with that of solid particles. On the other hand, difference of result near the peel sheering layer is larger than that of lower Reynolds number, therefore, there is a possibility that the difference cause measurement error for PIV using flow of high Reynolds number with peeling.