Viscous Growth Law in Bubble Coarsening: A Molecular Dynamics Perspective

We investigate the kinetics of bubble coarsening in a single component Lennard-Jones fluid using large-scale molecular dynamics simulations. A homogeneous high-temperature system is quenched below the critical temperature to induce the nucleation and growth of vapor bubbles within a dense liquid matrix. The structural evolution is characterized by two point correlation functions and the static structure factor, both of which exhibit dynamic scaling and sharp interfaces consistent with Porod law. The time-dependent characteristic length scale, extracted from the correlation function, shows a robust power law growth $\ell(t) \sim t^α$. Finite size scaling analysis across different system sizes yields $α\approx 1.0$, establishing that coarsening is dominated by viscous hydrodynamic interactions rather than classical diffusion-limited Ostwald ripening predicted by the Lifshitz-Slyozov-Wagner theory. These results provide atomistic evidence for fluid flow controlled coarsening in vapor-liquid systems and emphasize the need to go beyond diffusion-based theories to describe bubble dynamics in dense fluids.