120 高分子水溶液の非定常容器内旋回流れのPIV計測(S34-1 複雑流体の流れとその応用(1),S34 複雑流体の流れとその応用)  [in Japanese] 120 PIV Measurements of Unsteady Confined Swirling Flow of Polymer Solutions  [in Japanese]

This paper deals with flows of viscoelastic fluids such as aqueous polymer solutions, due to a rotating disc in a cylindrical casing. As the aqueous polymer solution, 0.1, 0.2, 0.5, 0.8 and 1.0 wt% polyacrylamide (PAA) solutions are used. The behavior of flow has been investigated using a flow visualization technique and a PIV measurement. The patterns of the secondary flow are classified using the Reynolds and elastic numbers. We found that a donut-type vortex or a spiral-type vortex was shed away from the rotating disc. In the region inside the spiral-type vortex, both tangential and radial velocity components were fluctuating periodically.