Microfluidic Studies On Snap-off During Imbibition Process

Imbibition process is particularly important for the exploitation of crude oil in fractured reservoirs. In order to understand the phenomenon in oil extraction process, occurring porous medium, there have been many studies using simple or complex cross-sectional shape of the capillary shape to simulate the process of sucking, and has made a series of research results have profound significance.In the imbibition process, snap-off phenomenon is particularly important, and has a great impact on the recovery of crude oil. Therefore, this phenomenon has gradually attracted research interest. Snap-off nature of the phenomenon at the time of the two immiscible fluids are present, the interaction between the two fluids such that the fluid phase which is non-wetting phenomenon of the clip forming droplets. For the oil mining process, when the wettability is wet, then the process of reservoir water flooding the porous medium is sucking process. In this process, when the snap-off occurs, the porous medium in the reservoir will produce small droplets. After the small droplets produced, can not easily be taken out, and will further lead to the reservoir pores are blocked, making the oil recovery decreased, resulting in a very adverse effect on the reservoir exploitation. Therefore, the snap-off phenomenon research, especially research will have an impact on its parameters, you can minimize the adverse effects of snap-off phenomenon for oil recovery, with significant implications for the exploitation of oil.In the snap-off factors for the study, the emerging microfluidic model has played a key role. For imbibition process of simulation, the two most commonly used experimental methods are core modeling and simulation within the capillary, but both methods have their own shortcomings. Capillary simulate a circular cross-section due to the capillary-based, does not have a real reservoir pore geometry representation, while the core simulation, is not conducive to real-time observation of phenomena. With respect to these two simulation methods, the microfluidic model because of its unique production process, can be artificially controlled cross-sectional shape of the pipe required for the simulation, and due to the transparency of the production of materials such phenomena can be observed and recorded directly through microscope and high-speed cameras to complete, more accurately to ensure the authenticity and accuracy of the experiment.