水煤浆管内流动的相似准数及其阻力特性

在分析水煤浆“滑移层”内流动的基础上,导出了表征水煤浆流动状态的相似准数——广义雷诺数Re_g。结果表明,它不仅适用于管内存在滑移的具有广义宾汉体和宾汉体性质的水煤浆流动,且同样适用于非牛顿流体中的宾汉体、幂律流体以及牛顿流体的无滑移流动。同时,水煤浆虽为液固两相非牛顿流体,但其层流流动的沿程能量损失系数的计算公式类似于牛顿流体的简单形式,即λ=64/Re_g。该式的计算精度令人满意。

SIMILITUDE CRITERION AND RESISTANCE CHARACTERISTICS OF COAL-WATER SLURRY FLOWING IN PIPE

Coal water slurry (CWS) with high mass concentration, as a kind of uniform suspension, has the property of non - Newtonian fluid, and there is a slip phenomenon when it flows in pipe. The similitude criterion, known as general Reynolds number Reg which can characterize the state of CWS flow in pipe, was put forward on the basis of analyzing the flow of the slip layer of CWS in pipe. The results show Reg holds good not only for the slip flow of CWS with the properties of general Bingham or Bingham fluid,but also for the no slip flow of other non -Newtonian fluid and Newtonian fluid. Moreover, for the non -Newtonian fluid of CWS consisting of water, coal powder and the chemical additives, the equation of the energy loss coefficient of CWS laminar flow in pipe has the same form as Newtonian fluid, that is λ=64/Reg. Compared with the experimental data, the accuracy of the equation is satisfactory in the experimental range.