Hydrogen, Vol. 4, Pages 556-572: Oxygen Bubble Dynamics in PEM Water Electrolyzers with a Deep-Learning-Based Approach
Hydrogen doi: 10.3390/hydrogen4030036
Authors: Idriss Sinapan Christophe Lin-Kwong-Chon Cédric Damour Jean-Jacques Amangoua Kadjo Michel Benne
Oxygen bubble accumulation on the anodic side of a polymer exchange membrane water electrolyzer (PEMWE) may cause a decrease in performance. To understand the behavior of these bubbles, a deep-learning-based bubble flow recognition tool dedicated to a PEMWE is developed. Combining the transparent side of a single PEMWE cell with a high-resolution high-speed camera allows us to acquire images of the two-phase flow in the channels. From these images, a deep learning vision system using a fine-tuned YOLO V7 model is applied to detect oxygen bubbles. The tool achieved a high mean average precision of 70%, confirmed the main observations in the literature, and provided exciting insights into the characteristics of two-phase flow regimes. In fact, increasing the water flow rate from 0.05 to 0.4 L/min decreases the bubble coverage (by around 32%) and the mean single-bubble area. In addition, increasing the current density from 0.3 to 1.4 A/cm2 leads to an increase in bubble coverage (by around 40%) and bubble amount.