Recent Developments on the Slow Viscoelastic Flow past Spheres and Bubbles
نویسندگان
چکیده
A review is presented covering the latest contributions to the slow viscoelastic flow past solid spheres and bubbles. The existing theoretical approaches are reviewed together with the available numerical methods. The proximity of container walls and its effect upon the motion of a sphere is also considered. Emphasis has been made on presenting recent experimental and numerical work intended to address some of the unresolved issues in this classic topic. Besides the so called “benchmark” problem of a viscoelastic fluid past a solid sphere centered on the axis of a long cylinder, this review addresses outstanding problems such as the wake behind the sphere, the negative wake, the depleted region effect as well as presenting some new results regarding the jump discontinuity in the velocity of rising bubbles.
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