壁面粗糙度对螺旋溜槽中矿浆流动及颗粒分离行为的影响

doi:10.12068/j.issn.1005-3026.2023.12.013

摘要/Abstract

摘要： 随着生产过程的进行，螺旋溜槽的壁面粗糙度并非定量且变化复杂，若控制不当则会严重影响物料分离效果.借助于前期确立的流场模型和颗粒相计算模型，系统考察壁面粗糙度对400mm螺旋溜槽中赤铁矿-石英矿浆流动和颗粒分离行为的影响.模拟结果表明:矿浆深度、雷诺数及流速具有明显径向分布差异和波动特性.随粗糙度增大，分选流体空间在粗糙度高度达到0.1mm及以上时严重收缩，层流分布范围扩大，过渡流范围变窄；速度与粗糙度具有明显相关性，在较高粗糙度下，主流和内环流波动增强，内环流出现明显间断；在0.1mm以下范围内增大粗糙度高度有利于粗粒赤铁矿向内缘区域聚集，粗粒赤铁矿和细粒石英的分离效率能维持高位，继续增大粗糙度，其分离效率显著降低；提高粗糙度加剧细粒赤铁矿在中、外区域的分布，细粒赤铁矿与石英的分离效率大幅降低.颗粒分离行为变化与流场特性改变密切相关.

关键词: 壁面粗糙度；螺旋溜槽；矿浆流；产物分割；分离效率

Abstract: With the process of production， the wall roughness of spirals is not quantitative and very complex， if it is not properly controlled， the material separation effect will be seriously affected. Based on the previously established spiral flow field model and particle phase computational model， the influence of the wall roughness on the slurry flow of hematite and quartz and particle separation behaviors in 400mm spirals was systematically investigated. The simulation results show that the slurry depth， Reynolds number， and flow velocity have notable differences in radial distribution and fluctuation characteristics. With the increase of roughness， the separation fluid space significantly contracts when the roughness height reaches 0.1mm or higher. the range of laminar flow distribution expands， while the transition flow range narrows. The velocity values exhibit a clear correlation with the roughness. Higher roughness intensifies the fluctuation of the main flow and the inner circulation， leading to noticeable disruption of the inner circulation. For roughness height below 0.1mm， increasing the roughness facilitates the convergence of coarse hematite towards the inner margin， maintaining a high separation efficiency for coarse hematite and fine quartz. However， the separation efficiency decreases significantly with the further increase of roughness. The increase of roughness intensifies the distribution of fine hematite in the middle and outer regions， resulting in a substantial decrease in the separation efficiency of fine hematite and quartz. The change of particle separation behaviors is closely related to the change of flow field characteristics.

Key words: wall roughness; spirals; slurry flow; product segmentation; separation efficiency

中图分类号:

TD45

周孝洪，高淑玲，孟令国，赵强. 壁面粗糙度对螺旋溜槽中矿浆流动及颗粒分离行为的影响[J]. 东北大学学报（自然科学版）, 2023, 44(12): 1769-1777.

ZHOU Xiao-hong， GAO Shu-ling， MENG Ling-guo， ZHAO Qiang. Influence of Wall Roughness on Slurry Flow and Particles Separation Behaviors in Spirals[J]. Journal of Northeastern University(Natural Science), 2023, 44(12): 1769-1777.

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