各向异性断块油藏水平井产能公式的推导

封闭性断块油藏在中国分布广泛,具有较多原始地质储量和剩余可采储量,因此评价断块油气藏水平井的产能方法具有重要意义。利用水电相似原理和等值渗流动阻力法,对于布井位置不同的断块油藏,在考虑油层渗透率各向异性条件下,得到了预测水平井产能的公式和水平井产量与水平井长度成正比的直线关系。通过应用实例表明,对于断块油藏,水平井布置在油层中央时的产能显著高于布置在边部的产能,这主要由于前者的流动阻力明显低于后者;不同垂向拟平面径向流的半径,对水平井产能的影响较小,且水平井的产能主要受控于线性流动区的阻力。

Derivation of productivity formulas for horizontal wells in anisotropic fault-block reservoirs

The sealed fault-block oil reservoirs are widely distributed in China, which possess plenty of original oil in place (OOIP)and residual recoverable reserves. Therefore, it is of great significance to evaluate the production methods of horizontal wells in fault-block hydrocarbon reservoirs. Based on water-electricity similarity principle and equivalent seepage dynamic resistance method, and in consideration of heterogeneous reservoir permeability, the prediction formulas of horizontal well productivity in the fault-block reservoirs with different well locations were obtained as well as the linear relationship of horizontal well production in direct proportion to horizontal well length. For fault-block oil reservoirs, the application cases show that the horizontal well productivity in central reservoir is significantly larger than that at the edges, which is mainly because the flow resistance of the former is obviously lower than that of the latter; the radial flow radius of different vertical quasi-plane has less influences on horizontal well productivity, while the horizontal well productivity is mainly controlled by the resistance of linear flow region.