水煤膏管内层流和过渡区的阻力特性  

Resistance Characteristics of Coal-water Paste in a Pipe at the Laminar Flow and Transition Zones

作　　者：卢平[1] 章名耀[2] 

机构地区：[1]南京师范大学动力工程学院,江苏南京210042 [2]东南大学洁净煤燃烧与发电技术教育部重点实验室,江苏南京210096

出　　处：《热能动力工程》2004年第3期260-264,共5页Journal of Engineering for Thermal Energy and Power

摘　　要：在分析非牛顿流体管内滑移流动机理的基础上 ,提出了通过计算水煤膏管内流动广义雷诺数Reg 来确定其阻力损失的方法。分析结果表明 :广义雷诺数不仅适用于管内存在滑移的非牛顿流体流动 ,同样适用于无滑移的非牛顿和牛顿流体流动。试验结果表明 :水煤膏管内定常流动的临界雷诺数约为 2 10 0 ;层流区采用广义雷诺数的沿程阻力系数的计算公式类似于牛顿流体的简单形式 ,即λ =6 4 /Reg;过渡区的阻力损失近似满足布拉休斯方程 ,λ =0 .316Re-0 .2 5g 。Based on the analysis of slip flow mechanism in a non-Newtonian fluid pipe the authors have come up with a method for determining the resistance losses of coal water paste through the calculation of a generalized Reynolds number Reg for the in-pipe flow of coal water paste. The results of an analysis indicate that the generalized Reynolds number is suitable not only for non-Newtonian fluid flow with slip being present in a pipe, but also suited for non-Newtonian and Newtonian fluid flow without a slip. Test results show that the critical Reynolds number of the steady flow of coal water paste in the pipe is approximately 2100. The formula for calculating resistance factors for laminar flow zones with the use of a generalized Reynolds number is similar to the simplified form for Newtonian fluid, namely, λ=64 Re g. The resistance loss at a transition zone can approximately satisfy Blasius equation, namely,λ=0.316Reg^(-0.25).

关 键 词：水煤膏 广义雷诺数 滑移现象 阻力特性 

分 类 号：TQ534.4[化学工程—煤化学工程]