现有边水突破时间预测模型都是基于中高渗油藏或不存在地层倾斜角,但实际边水油藏一定存在倾斜角,所以不能忽略由于倾斜角造成的重力作用的影响。基于油水两相渗流力学理论,建立符合实际情况的低渗倾斜边水油藏模型,且推导出低渗倾斜边水油藏水平井见水时间预测公式,其考虑了启动压力梯度、地层倾斜角、油水密度差、水平井到边水距离和水平井射孔长度等因素,并对影响因素进行了逐一分析。实例分析结果表明,与现有的预测边水突破时间计算公式相比,该计算方法预测的低渗倾斜边水突破时间更加接近实际情况。对于研究低渗倾斜边水舌进机理和低渗边水油藏生产管理工作具有重要的指导作用。
The existing predicting models are established on the bases of the middle-high permeability oil reservoirs or without the stratigraphicdip angles,but the actual edge-water reservoir must have the angle. So the effects of the gravity action resulted from the angle cannot be ignored. Based on the theory of water-oil two phase fluid mechanics,the low-permeability inclined edge-water reservoir model was established in line with the actual situation and moreover the predicting formula of the water breakthrough time was derivedfor the horizontal wells in the reservoir,considering the following factors: the starting pressure gradient,stratigraphic dip,oil-water density difference,distance between the horizontal well and edge water,the horizontal well perforated length and so on,and furthermore each influencing factor was analyzed one by one. The analysis results show that compared with the existing formulaof predicting the water breakthrough time,the calculating and predicting method in this paper is more close to the actual situation. It has important guiding roles for the studies on the mechanism of the edge water tonguing and the production management of the low-permeability inclined edge-water oil reservoir.