低渗透油藏中水平井的产能公式分析

用近似方法得出了各类边界供给油藏中的水平井产量公式。考虑启动压力梯度，根据水平井的椭球流态理论，通过平均质量守恒方法得到了椭球供给边界油藏中水平井的稳态产量近似公式，以及底水油藏中水平井的稳态产量近似公式；通过修正得到了含启动压力梯度的边水油藏中水平井的稳态产量公式。并给出了相应的无量纲产量公式和工程产量公式。分析表明，当启动压力梯度较小时，对产量的影响也很小，随着启动压力梯度的增大，影响增强，产

ANALYSIS ON PRODUCTIVITY FORMULA OF HORIZONTAL WELLS IN LOW PERMEABILITY RESERVOIR

Horizontal well production formula for various kind of boundary drainage reservoirs is obtained by using approximation. Considering the starting pressure gradient, the approximation formula of horizontal well static production are obtained for both ellipsoidal drainage boundary reservoir and bottom water reservoir based on ellipsoidal flow pattern theory and through average mass conservation method. After correlation, static production formula including starting pressure gradient is obtained for horizontal wells in edge water reservoir. And corresponding dimensionless production formula and engineering production formula are given. Analysis shows that, when the starting pressure gradient is relatively low, its effect on oil production is also small. With the increase of starting pressure gradient, the effect will become greater and production will decrease greatly.