温度影响下的充填料浆大流量管输流态演化

推导了综合雷诺数与料浆温度的数学模型,建立了料浆管道输送L管模型,基于数值模拟研究不同温度、管径及初始流速下的料浆输送阻力损失变化特征.结果表明:随料浆温度升高,综合雷诺数增加,经判断本试验料浆流态均为结构流;利用环管试验数据进行验证,料浆流动模型所测误差为4.9%及5.3%,说明该模型具有合理性与可靠性;随料浆温度升高,料浆输送阻力损失减小;随管径增大,料浆阻力损失降低,变化趋势逐渐减缓,平均减小率分别为24.5%和10.9%,阻力损失"拐点"管径为190 mm;随初始流速增加,料浆输送阻力损失增大,增加趋势随流速增大而变大,平均增长率分别是10.7%和17.7%,存在阻力损失"转折点"流速为2.4 m/s;建议矿山充填管道输送参数选取管径190 mm,初始流速2.4 m/s,温度保持在30~50℃.

考虑料浆温度影响的细尾砂膏体自流输送研究

为探究料浆温度影响下细尾砂膏体大流量自流输送特征,构建了细尾砂膏体自流输送水力坡度模型;基于数值模拟,分析了考虑料浆温度影响的不同流量、充填倍线细尾砂膏体自流输送水力坡度特征。所建立的水力坡度模型的测量误差为4.85%、2.21%,迭代计算56次、68次后收敛,表明该模型具有较高的可靠性及合理性。研究结果表明,随流量增加,细尾砂膏体的水力坡度增大,且充填倍线越小,增加趋势越趋于线性;膏体输送过程粗细颗粒间存在"非均匀干扰沉降"现象,随充填倍线增加,粗颗粒受细颗粒与料浆溶液影响而非均匀沉降,导致颗粒相互作用数量增多,水力坡度升高;膏体粗颗粒运移存在一定规律,屈服应力是影响颗粒运移的最关键因素,随充填倍线增加,膏体剪切流动区域面积增加,水力坡度升高;基于试验结果,为实现自流输送,建议输送流量选取220 m3/h,充填倍线选择5。

Large Eddy Simulation of Micro-Particles Transport with Different Mass Flow Rate in Turbulent Planar Jet Flow

The motion of micro-particles with different mass flow rate in the planer turbulent jet flow has been simulated, using LES method to obtain the flow vorticity evolution and Lagrangian method to track micro-particles. The re- suits showed that when the flow rate is small, the particles more likely to present in the vortex periphery, the dis- tribution pattern is similar to the flow pattern. When the flow rate is high, some particles will escape from the mo- tion region to the original static region, so that in the jet region, particles are relatively evenly distributed. When the flow field is full developed, the particles average concentration in the y direction affected by the mass flow rate relative slightly, the normalized mean particles concentrations at different flow rate were similar to Gaussian shape.