Slip effect of surface nanobubbles: A lattice Boltzmann study

Reducing the energy consumption caused by surface friction during fluid transport within channels is a critical concern in many fields. Surface nanobubbles, which are nano-scale gaseous domains attached universally to the fluid-solid interface, are a potential approach to achieve the large slip length and reduce the flow resistance that has attracted significant interest from scientists and engineers. A plethora of experiments have been conducted to address the issue of energy consumption resulting from surface friction, while also exploring methods to enhance fluid transport efficiency and illuminate how surface nanobubbles may influence fluid slip length. In this paper, we investigate the slip effect induced by the nanobubbles on channel surface using the chemical-potential lattice Boltzmann method, which satisfies the thermodynamic consistency and is fully discretized in time, space, and particle velocity. The numerical results are in excellent agreement with the experimental observations. Numerous simulations show that the presence of surface nanobubbles can increase the slip length by 2–3 orders of magnitude, significantly reducing the resistance of the channel wall to fluid flow. The slip effect can be effectively enhanced by increasing the nanobubble height, the bubble surface coverage and the wall surface hydrophobicity.