【摘要】 有效识别热水驱后期剩余油分布规律是开展泡沫辅助热水驱提高稠油油藏采收率的前提。利用二维可视化模型从宏观和微观角度解释了泡沫辅助热水驱提高采收率机理，进而采用Mask-CNN算法建立智能图像识别模型，定量分析剩余油分布规律。油水黏度差异导致热水驱过程中注采井间水窜严重，波及范围有限；泡沫可以对大孔道进行封堵，扩大热水波及体积，提高采出程度。图像识别结果表明，热水驱结束后模型剩余油饱和度约为62.5%,面积波及系数约为36.0%,驱油效率较高，约为75.6%,指进现象严重。氮气泡沫注入后波及区域比例增加到55.10%,氮气泡沫选择性封堵、扩大油藏波及效率效果显著；在氮气泡沫的辅助下，后续热水驱阶段剩余油饱和度降低至34.61%。氮气泡沫辅助热水驱可以有效提高稠油油藏热水驱后期采出程度，对实际开发具有重要的指导意义。更多还原

【Abstract】 Effective identification of the remaining oil distribution is essential for the successful implementation of foam flooding. This process plays a crucial role in enhancing heavy-oil recovery during the late stage of hot-water flooding. This study explained the mechanisms of improving the recovery by foam-assisted hot water flooding from macroscopic and microscopic perspectives using a two-dimensional visualization model. Based on the experiment images, the Mask-CNN algorithm was used to establish an intelligent image recognition model to quantitatively analysis the distribution of residual oil. Due to the difference in viscosity between oil and water, water flooding caused serious water channeling between injection and production wells during the hot water flooding process, with limited sweep area. After injecting foam, the foam plugs the large channels and expands the volume swept by hot water. Image recognition results showed that after hot water flooding, the residual oil saturation of the model was approximately 62.5%. In addition, the sweep coefficient was approximately 36.0%, with a relative high displacement efficiency of approximately 75.6%. This corresponds to severe fingering phenomenon in this stage. The proportion of the sweep area increased to 55.10% after nitrogen foam injection. The selective plugging by nitrogen foam were significant. With the assistance of nitrogen foam, the residual oil saturation in the subsequent hot water flooding stage decreased to 34.61%. Nitrogen foam-assisted hot water flooding can effectively improve the recovery rate in the late stage of pure hot-water flooding, providing important guidance for practical development.更多还原