泡沫流体在孔隙介质中的流动特点研究

Research on flowing characteristics of foam fluid in porous media

为了研究不同气液比及不同注入方式泡沫流体在长细管模型中产生的特点及运移规律以及端面封堵情况,通过长细管模型进行了注入泡沫流体在孔隙介质中的流动试验。试验结果证明,泡沫在多孔介质中流动,压差分布均匀,泡沫体系在渗透率20μm2孔隙介质中,能够形成较大的流动压差,并且不会形成端面堵塞,泡沫流动压差随气液比的增大而增大,泡沫压差形成的速度随气液比的增大而增快,形成稳定压差的时间变短;混合式注入泡沫形成的压差由前向后运动,交替式注入气体及泡沫剂溶液首先在中部形成压差,逐渐向两端扩展,混合式注入形成泡沫封堵的时间明显少于交替式注入。泡沫流体适合于油藏驱油,不会形成端面封堵,且混合式注入优于交替式注入。

The experiment is conducted to test the flowing characteristics of the foam fluid in porous media injected by the long slim tube model. The aim is to research the flowing characteristics, the migrating laws, and the end jamming conditions of the foam fluid of different gas - liquid ratios and different injecting manners in the long slim tube model. Experimental results show that the foam fluid features in homogeneous distribution of pressure difference （PD） when it flows in porous media. The PD increases when the foam fluid flows in the porous media of which the permeability is 20 μm^2, But end plugging does not happen. The PD and the velocity of producing PD increase with the gas - liquid ratio. It takes less time to produce stable pressure difference. The PD based on mixed injection of foam fluid moves from the top to the end, while the PD based on alternative injection of gas and foam solution is firstly produced in the middle and then extends towards two ends, The time of forming foam jam based on mixed injection is obviously shorter than that based on alternative injection. Foam fluid is suitable for oil displacement of reservoirs, and end jam will not be produced. Mixed injection is superior to the alternative injection.