Liquid directional transport surface applied to the spacecraft fluid management system: Fundamentals and prospect analysis

Liquid directional transport surfaces have the ability to control the movement of liquids in specific directions, making them highly applicable in various fields such as heat transfer, fluid management, microfluidics, and chemical engineering. This review aims to summarize the research progress on liquid directional transport surfaces and spacecraft fluid management devices. Among the different liquid control technologies available, certain surface design methods based on principles of fluid dynamics under microgravity show remarkable potential for space fluid management. Precise fluid management is crucial for the in-orbit operation of spacecraft. Utilizing surface tension effects represents the most direct and effective approach to achieve directional liquid transport in space. The intrinsic flow characteristics of the two-dimensional plane of directional transport surfaces are advantageous for managing fluids in the confined spaces of spacecraft. By analyzing the functional characteristics of these liquid directional transport surfaces, we assess their feasibility for integration into spacecraft fluid management devices. Considering the features of the space environment, this review also provides design guidelines for liquid directional transport surfaces suitable for use in spacecraft fluid management devices, serving as a significant reference for future research.