采用并联岩心组合方式确定了不同渗透率级差岩心的注入能力和分流能力特征,通过泡沫粒径测量实验和发泡多孔介质的恒速压汞实验研究了泡沫与孔隙结构的匹配关系.结果表明:岩心渗透率级差为6后分流量比值大于1,当主流喉道直径与泡沫平均直径比值大于0.911时分流率为0.98,出现等流度流动;泡沫平均直径与主流喉道直径比值约为1∶1时,泡沫能够达到较好的孔喉封堵效果,实现剖面反转或等流度流动;在分流量和注入压力的综合影响下,泡沫粒径与喉道半径比为0.826,进而确定合理的分流率比例为0.777.研究确定了岩心渗透率级差对泡沫封堵能力和分流率比例的影响程度.
The injecting and shunting capacities of various permeability differential cores are determined by the parallel core combination, and the matching relations between the foam and pore structures are researched through the experiments of the bubble size measurement and constant-speed mercury injection in the foam porous media. The results show that when the core permeability differential in more than 6, the fractional flow ratio is higher than 1, when the ratio between the mainstream throat diameter and average bubble diameter is greater than 0. 911, the fractional flow ratio is 0. 98, thus the iso-mobility flow appears; while the diameter ratio reaches approximately 1 : 1, much throat sealed effects are obtained with the help of the foam, and moreover the profile inversion or isomobility flow are realized; comprehensively influenced by the fractional flow ratio and injection pressure, the ratio between the bubble size and throat radius is 0. 826, the reasonable fractional flow ratio is confirmed to be 0. 777.The influence degrees of the core permeability differential on the foam sealing ability and fractional flow ratio are determined by the study achievements stated above.