考虑井筒压降的水平井产能影响因素研究

Influencing factors to horizontal well productivity considering wellbore pressure drop

水平井井筒内压降对水平井生产动态有较大影响,特别是当水平段较长时,将导致水平井筒末端油藏和井筒的压降很小,甚至为零。根据质量守恒定律和动量定理,在建立裸眼完井水平井筒内单相变质量流动压降方程的基础上,建立与油藏耦合的产能计算模型,分析了各因素对水平井产能的影响。通过研究发现,对于具体油藏具体水平井存在一个最优的水平段长度,同时水平井井径、流体粘度、流体密度、油层厚度、水平段到油藏底部距离、水平渗透率和垂向渗透率等参数均会对水平井的产能造成一定的影响。

The pressure drop in horizontal wellbore has a big impact on production performance. Especially when horizontal section is long,the pressure drop at toe may be very small or even zero. A reservoir-coupling productivity model has been established based on the pressure drop equation for single-phase variable mass flow within an open horizontal wellbore according to the mass conservation law and the momentum theory to analyze the influencing factors to horizontal well productivity. The study reveals that there is an optimal length of horizontal section for a particular horizontal well in a particular reservoir. In addition,parameters such as horizontal well diameter,fluid viscosity,fluid density,reservoir thickness,the distance from horizontal section to the bottom of the reservoir,horizontal permeability and vertical permeability will have certain effects on horizontal well productivity.