非牛顿流体偏心环形空间螺旋流的速度分布

VELOCITY DISTRIBUTION OF HELICAL FLOW OF NON-NEWTONIAN FLUID IN ECCENTRIC ANNULI

从理论上建立了双极坐标系下非牛顿流体偏心环空螺旋流的控制方程，其为用流函数和轴向速度表示的四阶非线性变系数非齐次偏微分方程组。给出了上述方程组的有限差分法数值求解步骤，并以水和ＣＭＣ水溶液室内实验数据为例，计算和分析了非牛顿流体偏心环空螺旋流的速度分布规律，结果表明：非牛顿流体偏心环空螺旋流中存在二次流区，且影响二次流区域大小的主要因素是偏心距。

The governing equations of the helical flow of non-Newtonian fluid in eccentric annuli are theoretically established.They are the 4th order nonlinear nonhomogeneous partial differential equations with variable coefficients expressed by the stream function and axial velocity in the bipolar coordinate system.The calculation steps of the finite difference method of these equations are given.Given the examples of experimental data of water and CMC aqueous sol ution from laboratory,the velocity distribution functions of the helical flow of non-Newtonian fluid in eccentric annuli are calculated and analyzed.The results show that there is a secondary flow involved in the helical flow of the non-Newtonian fluid in eccentric annuli,and that the eccentricity is a major factor to exert influences on the size of the region of secondary flow.