Bridging scales in multiscale bubble growth dynamics with correlated fluctuations using neural operator learning

TL;DR

This paper introduces a neural operator model that unifies microscale and macroscale bubble growth dynamics, accurately capturing nonlinear behavior and correlated fluctuations across scales using deep learning techniques.

Contribution

The study develops the first neural operator framework that bridges microscale stochastic fluid models with continuum models for bubble dynamics, incorporating correlated fluctuations.

Findings

Achieves 99% accuracy in bubble radius prediction under varying pressures.

Successfully captures size-dependent stochastic fluctuations in microscale bubble growth.

Demonstrates effective multiscale modeling of bubble dynamics with neural operators.

Abstract

The intricate process of bubble growth dynamics involves a broad spectrum of physical phenomena from microscale mechanics of bubble formation to macroscale interplay between bubbles and surrounding thermo-hydrodynamics. Traditional bubble dynamics models including atomistic approaches and continuum-based methods segment the bubble dynamics into distinct scale-specific models. In order to bridge the gap between microscale stochastic fluid models and continuum-based fluid models for bubble dynamics, we develop a composite neural operator model to unify the analysis of nonlinear bubble dynamics across microscale and macroscale regimes by integrating a many-body dissipative particle dynamics (mDPD) model with a continuum-based Rayleigh-Plesset (RP) model through a novel neural network architecture, which consists of a deep operator network for learning the mean behavior of bubble growth subject to pressure variations and a long short-term memory network for learning the statistical features of correlated fluctuations in microscale bubble dynamics. Training and testing data are generated by conducting mDPD and RP simulations for nonlinear bubble dynamics with initial bubble radii ranging from 0.1 to 1.5 micrometers. Results show that the trained composite neural operator model can accurately predict bubble dynamics across scales, with a 99% accuracy for the time evaluation of the bubble radius under varying external pressure while containing correct size-dependent stochastic fluctuations in microscale bubble growth dynamics. The composite neural operator is the first deep learning surrogate for multiscale bubble growth dynamics that can capture correct stochastic fluctuations in microscopic fluid phenomena, which sets a new direction for future research in multiscale fluid dynamics modeling.