竖直管道中固—液两相流动流态化实验探讨

主要探讨竖直管道中不同颗粒级配、流体流速条件下的固-液两相流动的流态化规律.首先通过量纲分析获得关键控制参数,然后以玻璃珠(粒径:0.25 mm～2.0 mm)、粉细砂(d10=0.044 mm)两种固体和水为实验介质,开展了两相流动流态化实验,考虑流体流速(相对于管道雷诺数介于640～3 300之间)和颗粒级配的影响.通过分析发现:具有均匀粒径分布的玻璃珠床,床层膨胀高度随流速的增加而增加,流速与浓度的对数呈线性关系,与Richardson--Zaki公式一致;具有较宽粒径分布的粉细砂,细颗粒随水流逐渐流出管道,剩余颗粒质量与雷诺数呈指数递减趋势.

EXPERIMENTAL STUDY OF FLUID-SOLID TWO-PHASE FLOW IN A VERTICAL TUBE

This paper presents an experimental study of the solid-water two-phase flow with different solid grain size distributions and flow velocities. First, the controlling parameters are obtained through the dimensional analysis, then a two phase flow is created by using glass beads(grain size:0.25 mm-2.0mm) and sands(d₁₀=0:044 mm), respectively. The effects of the Reynolds number Re(640-3300) and the solid grain size are investigated. The results show that for the glass bead bed of mean grain sizes, the height of the bed in the tube increases linearly with the Reynolds number. For the sands of a wide particle gradation range, the small grains are flushed out of the tube and the residue mass decreases with the Reynolds number exponentially. The results might help the evaluation of the elevation of the soils containing the gas hydrate under the seafloor.