某全尾砂膏体流变参数测量及其流变模型优化

发布时间：2018-02-28 19:15

本文关键词： 全尾砂膏体剪切应力松弛流变参数 Bingham塑性体 Bingham伪塑性体　出处：《金属矿山》2017年12期 　论文类型：期刊论文

【摘要】：全尾砂膏体在管道输送设计时需要选取合适的非牛顿流变模型。但全尾砂膏体在进行流变参数测取实验时,其颗粒种类、粒度分布及其内部结构不能保证在每一份测量试验下均相同,故全尾砂膏体流变参数测量重复率较低且其流变模型选择不够精确,直接影响了管道输送阻力值的大小。针对以上问题,基于全尾砂膏体在恒定剪切速率下存在剪切应力松弛的特性,待其剪切流动达到"等结构"状态后再测量相应的剪切应力-剪切速率关系。基于多次测量均值法降低流变参数测量的随机误差,并通过模型多参数依次拟合法求取最适宜的流变模型。研究结果表明,本次实验最优模型为Bingham伪塑性体模型,最优流变参数为幂律指数n=0.7,屈服应力82.24 Pa,稠度系数4.941 Pa·s,各样品组之间流变参数拟合差异较小,实验方案能够获取较精确的流变模型。
[Abstract]:It is necessary to select suitable non-Newtonian rheological model for the design of the whole tailings paste in pipeline transportation. However, when the rheological parameters of the whole tailing paste are measured, the particle types of the paste are determined. The particle size distribution and its internal structure can not be guaranteed to be the same in every measurement test, so the measuring repetition rate of rheological parameters of whole tailing paste is low and the choice of rheological model is not accurate enough. The resistance value of pipeline transportation is directly affected. In view of the above problems, based on the characteristics of shear stress relaxation of whole tailing paste at constant shear rate, The relationship between shear stress and shear rate is measured after the shear flow reaches the state of "equal structure". The random error of rheological parameter measurement is reduced based on the method of multiple mean measurements. The most suitable rheological model is obtained by multiple parameter fitting. The results show that the optimal model of this experiment is Bingham pseudoplastic body model. The optimal rheological parameters are power law exponent nong 0.7, yield stress 82.24 Pa, consistency coefficient 4.941 Pa 路s, and the difference of rheological parameters fitting among different sample groups is small. The experimental scheme can obtain a more accurate rheological model.
【作者单位】：北京科技大学土木与资源工程学院;金属矿山高效开采与安全教育部重点实验室;
【基金】：国家重点研发计划项目(编号:2016YFC0600709) 国家自然科学基金项目(编号:51774039)
【分类号】：TD853.34

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