基于滑移效应的水煤浆膏体管道输送阻力计算

Transport resistance characteristics of coal-water slurry considering effects of wall slip

随着煤化工产业的发展,煤炭如何高效清洁输送成为研究的热点。利用管道水力输送高浓度水煤浆具有投资少、节能环保等明显优势。由于小管径试验操作更加方便,更加节省物料,试验室中常用小管径进行工艺参数试验。试验研究了质量浓度为53%和58%的高浓度水煤浆在管径为50,47,32和29 mm管道中的流动特性。推导了滑移条件下不同流型流体的流变参数计算式,并基于滑移效应分析,得到了水煤浆的阻力系数。通过均质流阻力计算式得到高浓度水煤浆的阻力,计算结果表明,水煤浆的流变模型符合Herschel-Bulkey模型,考虑滑移效应条件下,高浓度水煤浆阻力系数与广义雷诺数存在一定关系,阻力可用均质流公式进行计算。

With the development of coal chemical industry,efficient and clean transportation of the coal has become a real research subject.Using pipelines to convey high concentration coal-water slurry has obvious advantages,such as less investment,energy saving and environmental protection.Research on the resistance characteristics of the coal-water slurry is of great significance to the conveying experiment design.Because small-diameter pipe experiment is more convenient to operate and save more materials,the small-diameter pipe is often used for simulation in the laboratory.The flow characteristics of high concentration coal-water slurry with the mass concentrations of53%and58%in the pipes with a diameter of50,47,32,and29mm were tested in this study.The formula of rheological parameters for different flow regimes under the slip condition is derived,and the resistance coefficients of the coal-water slurry are obtained based on the analysis of the slip efficiency.The resistance of high concentration coal-water slurry is calculated using the calculation formula of homogeneous flow resistance.Compared with other formulas,the homogeneous flow formula is most consistent with the experimental results.The calculated results show that the rheological model of CWS conforms to the Herschel-Bulkey model.Under the conditions of the sliding effects,the relationship between the resistance coefficients of the high concentration coal-water slurry and the generalized Reynolds number can be expressed as a formula,and the resistance can be calculated by the homogeneous flow formula.