幂律流体偏心环空轴向层流流动的速度分布

VELOCITY PROFILE OF AXIAL LAMINAR FLOW FOR POWER LAW FLUIDS THROUGH ECCENTRIC ANNULI

利用控制体积法对幂律流体偏心环空轴向层流流动的基本方程进行了离散化处理，并用ＡＤＩ方法进行了求解。计算了流场中的速度分布和窄、宽边速度比等流场参数。在考虑了周向应力的情况下，分析了流体流变参数及环空几何参数对速度分布等流场参数的影响。偏心度的影响最为明显，偏心度增大时，窄、宽边的速度比减小。在钻井过程中，为了提高井眼的洁净度，应减小钻杆的偏心度。当偏心度较大时。

By using volume control method, the basic equations of axial laminar flow for power law fluids in eccentric annuli was seperated and sovled by ADI (Alternate Direction Iterail) method. The flow field parameters, such as velocity profile and velocity ratio between narrow and wide sides, were calculated. The influnces of annuli geometry and fluid behavior on them were analysed. The numerical results show that the velocity ratio between narrow and wide sides is not proportional to eccentricity, and negligence of circumferential stress will lead to a significant error especially at bigger eccentricity.