Characteristics of oxygen bubble transport process in proton exchange membrane electrolysis cell
（1. Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan， Hubei 430070, China; 2. Hubei Collaborative Innovation Center for Automotive Components Technology, Wuhan University of Technology, Wuhan, Hubei 430070, China; 3. Clean Energy Research Centre, Department of Chemical and Biological Engineering, University of British Columbia, Vancouver V6T 1Z3, Canada)
摘要 研究了质子交换膜电解池(proton exchange membrane electrolysis cell，PEMEC)阳极流场内的氧气泡运动特性，采用VOF(volume of fluid)方法分析了多孔输运层（porous transport layer,PTL）表面接触角、液态水流速、氧气产生速率及PTL孔径对氧气泡在流道中运动特性的影响.结果表明：PTL处理为亲水性有利于气泡脱离，降低表面气体覆盖率，促进液态水到达催化层；高的液态水流速会减小气泡脱离时间及脱离体积，降低PTL表面气体覆盖率及容积含气率，促进气泡从流道中排出；气体生成速率增大会提高流道容积含气率和PTL表面气体覆盖率，不利于电解池的运行；随PTL孔径增大，气泡脱离体积增大，脱离时间先减小后增加.
Abstract： The dynamic behaviors of a single oxygen bubble in the anode flow field of proton exchange membrane electrolysis cell （PEMEC）were investigated. The effects of porous transport layer (PTL) contact angle, water flow rate, oxygen generating rate and pore size on the motion characteristics of oxygen bubbles in the flow channel were analyzed by the volume of fluid (VOF) method. The simulation results show that hydrophilic PTL is beneficial to detach bubble, reduce the gas coverage ratio and promote the reactants to catalytic layer. High liquid water flow rate can reduce the bubble detachment time and volume and lower the surface gas coverage ratio and volume gas content to promote the bubble exhausting from the channel. The increasing of gas generation rate can increase the volume gas content and gas coverage ratio, which is not conducive for the performance. With the increasing of pore size, the bubble detachment volume is increased, and the detachment time is decreased with latter increasing.
