多分支水平井的产能计算

为了使多分支水平井产能公式更符合实际,从三维势函数的定义推导出无界地层中多分支水平井三维稳态渗流速度势分布,再根据镜像反映和势叠加原理,推导出了具有边界条件下多分支水平井的三维稳定势分布.以底水驱油藏多分支水平井三维稳定势为例,利用辛卜生公式对势函数进行简化处理,再进行坐标平移和坐标旋转,得出了底水驱油藏多分支水平井三维稳定产能公式.公式中考虑了多分支水平井在油藏中的位置及油层各向异性等因素对水平井产能的影响,引入了多分支水平井各分支流动阻力修正系数.对一口井进行了实例计算,表明新公式求解方法简洁,计算结果符合实际.

Productivity of multiple-branched horizontal wells

To make the function of multi-branched horizontal well productivity match with reality perfectly, in this paper, a three-dimensional steady flow velocity potential function for a horizontal well with multiple-branched is derived under unbounded formation. Imaging and superposition principle are applied to derive three-dimensional steady flow velocity potential distribution for a horizontal well with multiple-branched under bounded formation. In 3D steady state potential distribution in a horizontal well from bottom water drive reservoirs, a new formula for calculating the productivity of multiple branched horizontal well is developed. The effects of the horizontal well position relative to water-oil contact and permeability anisotropy on productivity are considered. A modified factor of flow resistance is introduced into the formula. It makes the formula simpler and more practical. An example of calculation shows that the new formula is stricter and quicker and its results match well with practical data.