Liquid-Infused Surfaces with Trapped Air (LISTA) for Drag Force Reduction

Area of Science:

• Fluid dynamics
• Surface science
• Materials science

Background:

• Superhydrophobic (SHP) surfaces reduce drag by trapping air, but are unstable under pressure and prone to air dissolution.
• Liquid-infused surfaces (LIS) replace air with lubricant to improve stability, but show limited drag reduction for low-viscosity fluids like water.
• Existing LIS designs struggle to provide significant drag reduction for water due to viscosity differences.

Purpose of the Study:

• To design and evaluate a novel surface, liquid-infused surfaces with trapped air (LISTA), for enhanced drag reduction in low-viscosity fluids.
• To address the limitations of SHP and LIS surfaces in maintaining air layers and lubricant stability.
• To investigate the drag reduction performance of LISTA surfaces for water flow.

Main Methods:

• Developed LISTA surfaces by trapping a layer of air beneath an infused lubricant within porous structures.
• Utilized double-reentry designs to enhance meniscus stability in the water-oil-air three-phase system.
• Solved the biharmonic equation to predict the drag reduction performance of the LISTA surfaces.

Main Results:

• LISTA surfaces demonstrated improved drag reduction compared to traditional LIS surfaces for water flow.
• The novel design effectively reduced frictional forces by maintaining a stable air-lubricant interface.
• LISTA designs showed a 20-37% performance advantage over LIS counterparts in proof-of-concept studies.

Conclusions:

• LISTA surfaces represent a promising advancement for achieving significant drag reduction in low-viscosity fluids like water.
• The combination of trapped air and infused lubricant overcomes the limitations of previous surface designs.
• Further research into LISTA surfaces could lead to more efficient fluid transport and reduced energy consumption.