Phase field modelling of the growth and detachment of bubbles in a hydrogen electrolyzer

TL;DR

This paper presents a phase field model to simulate hydrogen bubble growth and detachment in electrolyzers, analyzing how parameters like contact angle and voltage influence bubble behavior.

Contribution

It introduces a numerical phase field model specifically for bubble dynamics in electrolyzers, incorporating effects of contact angle, gravity, and electrochemical conditions.

Findings

Detachment time varies with static contact angle and applied voltage.

Bubble volume at detachment depends on electrochemical parameters.

Model predicts bubble behavior under different operational conditions.

Abstract

We develop and implement numerically a phase field model for the growth and detachment of a gas bubble resting on an electrode and being filled with hydrogen produced by water electrolysis. The bubble is surrounded by a viscous liquid, has a prescribed static contact angle and is also subject to gravitational forces. We compute, as a function of the static contact angle, the time at which the bubble detaches from the substrate and what volume it has at that time. We also investigate de dependence of the detachment time on other parameters such as the applied voltage and the hydrogen ion concentration at the fluid bulk.