Computational Investigation on the Air Bubble Dispersion of Air Lubrication System Configurations for Hydrodynamic Drag Reduction in a Ro-Ro Vessel

This study investigates the influence of Air Lubrication System (ALS) nozzle configurations on air bubble dispersion and hydrodynamic drag reduction in a Ro-Ro vessel. The research hypothesis states that the orientation, injection angle, and arrangement of air injection nozzles along the hull bottom significantly affect the distribution and stability of air bubbles beneath the hull, which in turn determines the effectiveness of frictional resistance reduction. The dataset was generated using Computational Fluid Dynamics (CFD) multiphase simulations. The simulations modeled the interaction between water and injected air under various nozzle configurations and flow conditions. The resulting data include velocity fields, pressure distribution, air mass fraction, and hydrodynamic resistance components, providing detailed insight into bubble dispersion behavior beneath the hull.
The results indicate that bubble dispersion patterns are strongly influenced by nozzle configuration and surrounding hydrodynamic conditions. Certain configurations produce a more uniform and stable air layer along the hull surface, which enhances skin friction reduction, while irregular bubble dispersion or rapid bubble escape reduces lubrication effectiveness. The findings also highlight that vessel speed and hull geometry contribute to the stability and transport of injected air bubbles. The dataset can therefore be used to interpret the relationship between ALS design parameters and multiphase flow behavior, serving as a reference for validating numerical ALS models and supporting further optimization of ALS configurations in ship design to improve hydrodynamic efficiency.