摘要
通过改变管径、温度、煤粉粒度和浓度,在中试规模的输送装置上研究水煤浆直管内的滑移流动规律,联合采用Mooney滑移修正方法和Tikhonov正则化方法确定浆体壁面滑移特性。结果表明,随温度和固相粒径的增大,临界剪切应力降低,壁面滑移速度显著增加;浓度越高,临界剪切应力及产生相同滑移速度所需的壁面剪切应力越大,温度升高对临界剪切应力和屈服应力的降低越显著;低壁面剪切应力下的滑移贡献率主要取决于临界剪切应力及屈服应力的相对大小,高壁面应力下主要取决于壁面滑移速度和浆体真实流变特性。
By changing pipe diameter, temperature, solid particle size and concentration, slip flow behavior of coal-water slurries in pipelines was investigated on a pilot scale flow facility. A procedure combining the traditional Mooney slip-correction method with numerical technique based on Tikhonov regularization was used to determine wall-slip behavior. The results suggested that when temperature and solid particle size increased, critical shear stress decreased and slip velocity increased significantly. At a high concentration, there were larger critical shear stress and higher wall shear stress needed to yield the same slip velocity than low concentration slurry. Increasing temperature at a higher concentration resulted in rapid decrease in critical shear stress and yield stress. Slippage contribution depended mainly on the difference between yield stress and critical shear stress at low wall shear stress, and on both wall-slip velocity and rheological behavior of bulk slurry at high wall shear stress.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2008年第9期2206-2213,共8页
CIESC Journal
基金
国家重点基础研究发展计划项目(2004CB217701)~~
