水平井不同倾角井筒临界携砂流速对比实验及其拟合应用

COMPARING EXPERIMENTS AND THEIR MATCHING APPLICATION OF THE BOREHOLE CRITICAL SAND-CARRYING VELOCITY IN THE HORIZONTAL WELL WITH DIFFERENT PITCHING ANGLES

井筒中的携砂流速是石油工程领域携砂生产问题的主要设计参数之一,目前国内外学者针对垂直井的携砂流速研究较多,但对水平井中不同倾角井段的携砂流速变化规律及其影响因素关注较少。基于上述问题,针对井筒由水平至垂直的全倾角变化过程,使用携砂规律模拟实验装置进行了井筒倾角0°~90°、流体黏度1~50 m Pa·s、石英砂和陶粒颗粒尺寸0. 08~0. 4 mm、井筒内径40~100 mm条件下的井筒携砂流速对比实验,得到了不同井筒倾角下携砂流速与流体黏度、颗粒尺寸、颗粒密度、井筒内径的敏感性关系和携砂流速变化规律。使用实验数据拟合得到水平段、倾斜段、垂直段井筒携砂流速的经验模型,结果表明,在其他实验条件相同的情况下,井筒在0°,30°,45°,75°,90°时的携砂流速之比为1. 71∶3. 35∶2. 86∶2. 28∶1。基于实验现象与拟合结果,给出了修正现有特征流速的流程和方法,以完成合理的携砂流量设计。

Sand carrying velocity in the wellbore is one of the main design parameters for the sand carrying production in the field of petroleum engineering. At present, there are many studies on the sand carrying velocity in the vertical wells for the scholars at home and abroad, but the variation law of the sand carrying velocity in the horizon- tal well section with different inclination angles and its influencing factors are seldom concerned. Based on the above problems, aimed at the whole inclination-angle changing the help of the simulation experimental device for the process from horizontal to vertical for the wellbore, with sand-carrying laws, the sand carrying flow rate comparison ex-periments in the well wellbore were carried out under the conditions of 0-90° borehole inclination angle, 1-50 mPa ~ s fluid viscosity, sensitive relationship and c 0. 08-0. 4 mm quartz sand and the ceramiste size, 40-100 mm borehole diameter, the hanged laws of the sand carrying velocity were achieved between the sand flow velocity and the fluid viscosity, particle size, particle density, borehole inner-diameter at different borehole inclination an- gles. By means of the experimental data matching, the empirical models of the horizontal, inclined and vertical wellbore sand carrying velocity were obtained. The results show that under the same condition of the other experi- mental conditions, when the wellbore pitching angles are 0° , 30° , 45° , 75° , 90° , the sand carrying velocity ratios are about 1.71 ： 3.35 ： 2. 86 ： 2. 28 ： 1. Based on the experimental phenomena and the matched results, the flow chart and method of the corrected existing characteristic flow rate were presented, thus the reasonable design of the sand conveyed amount can be completed.