139 Shear-thinning性流体中に混入した微小気泡除去方法の検討(S34-4 複雑流体の流れとその応用(4),S34 複雑流体の流れとその応用)  [in Japanese] 139 A Study of Removing Small Bubbles from Shear-thinning Fluids  [in Japanese]

An enhancement of removing bubbles from shear-thinning fluids was studied. We have found that periodical pressure changes in the shear thinning fluids have a good effect on enhancing bubbles rising, where local shear flows occur in the vicinity of bubbles due to a change in volumes of bubbles, and then local apparent viscosities of the surrounding liquids are lowered, therefore drag forces are reduced. The pressure inside a closed test cell was controlled by vibrating a thin-film set on the cell. We observed that the bubble rising velocities with periodical pressure changes were faster over 200 times in some case than its natural bubble rising velocity.