Yield stress fluid flow past a circular cylinder confined in a channel
Abstract
This paper presents a numerical investigation of flow characteristics of yield stress fluid over a confined cylinder at Re=50-100. Sediment suspension with kaolinite mass concentration from c=15-28.5% are targeted. To describe the yield stress effect, the Bingham-Papanastasiou model is utilized. Various flow features of the yield stress fluid, i.e., formation of solid-like regions, streamlines, vorticity distribution, and drag force are reported and analyzed. In detail, the suspension flow is found to be steady within the condition range studied. With a very large kaolinite fraction (i.e., c=28.5%), the flow is in a creeping mode without downstream circulation developed. Moreover, solid-like regions are found to be greatly affected by the Reynolds number and yield stress effect. Additionally, the flow behaviors confined in a channel are significantly different from those produced by the unconfined one (infinite blockage). Furthermore, the drag coefficient is found to strongly depend on Reynolds number and kaolinite fraction.
Moraref