Numerical investigation of non-condensable gas effect on vapor bubble collapse

TL;DR

This study numerically explores how non-condensable gas within vapor bubbles influences bubble collapse dynamics, pressure waves, and rebound, providing a validated multi-component model for accurate simulation of these effects.

Contribution

The paper introduces a validated multi-component model that captures the impact of non-condensable gas on vapor bubble collapse dynamics and shock wave behavior.

Findings

Non-condensable gas dampens pressure waves and enhances bubble rebound.

The model accurately predicts the effect of gas on shock wave damping.

Simulations show the importance of gas in bubble collapse behavior.

Abstract

We numerically investigate the effect of non-condensable gas inside a vapor bubble on bubble dynamics, collapse pressure and pressure impact of spherical and aspherical bubble collapses. Free gas inside a vapor bubble has a damping effect that can weaken the pressure wave and enhance the bubble rebound. To estimate this effect numerically, we derive and validate a multi-component model for vapor bubbles containing gas. For the cavitating liquid and the non-condensable gas, we employ a homogeneous mixture model with a coupled equation of state for all components. The cavitation model for the cavitating liquid is a barotropic thermodynamic equilibrium model. Compressibility of all phases is considered in order to capture the shock wave of the bubble collapse. After validating the model with an analytical energy partitioning model, simulations of collapsing wall-attached bubbles with different stand-off distances are performed. The effect of the non-condensable gas on rebound and damping of the emitted shock wave is well captured.