ABSTRACT
To improve the recovery rate of oil in the formation, oil recovery technology has been continuously studied. Considering the experimental cost and data measurement in oil recovery research, laboratory oil recovery is the most effective method. The rock core model used in the simulation directly affects whether the research results are credible. However, the current three-dimensional rock core model manufacturing methods and corresponding models lack of reproducible, customizable, and visualized characteristics. In this study, a reproducible rock core model of microsphere accumulation based on the structure of natural rock core was designed and manufactured by microstereolithography. Oil recovery experiments and simulation studies show that the rock core model has similar flow characteristics to natural rock cores. In addition, resin rock core models with different structures and hydrogel rock core models with deformability are also manufactured by microstereolithography and used for simulation analysis. This research provides an effective and reproducible rock core structure model for the experiment of oil recovery research.
ABSTRACT
In this study, we propose a highly efficient robot platform for pollutant adsorption. This robot system consists of a flapping-wing micro aircraft (FWMA) for long-distance transportation and delivery and cost-effective multifunctional Janus microrobots for pollutant purification. The flapping-wing micro air vehicle can hover for 11.3 km with a flapping frequency of approximately 15 Hz, fly forward up to 31.6 km/h, and drop microrobots to a targeted destination. The Janus microrobot, which is composed of a silica microsphere, nickel layer, and hydrophobic layer, is used to absorb the oil and process organic pollutants. These Janus microrobots can be propelled fast up to 9.6 body lengths per second, and on-demand speed regulation and remote navigation are manageable. These Janus microrobots can continuously carry oil droplets in aqueous environments under the control of a uniform rotating magnetic field. Because of the fluid dynamics induced by the Janus microrobots, a highly efficient removal of Rhodamine B is accomplished. This smart robot system may open a door for pollutant purification.
