针对质子交换膜燃料电池微孔层中气液两相流传输问题,提出一种改进的随机数值方法来进行三维微孔层微结构重构,并利用孔尺度模型和格子玻尔兹曼方法分别模拟不同微观结构下微孔层内部的气-液传输。通过对比有效气体扩散率和饱和度,研究碳球直径、播种率和聚四氟乙烯含量对气-液传输的影响。结果表明,微孔层中有效气体扩散率随孔隙率和碳颗粒尺寸的增加而增加,随聚四氟乙烯体积分数和播种率的增大而降低;液态水传输能力随碳颗粒尺寸的增加而增加,随着播种率的增大而减小;液态水传输性能在聚四氟乙烯体积分数为15%时达到最优,这可为膜电极中的传输特性优化设计提供理论依据。
Abstract
An improved stochastic numerical method is proposed to reconstruct the three-dimensional microporous layer （MPL） model. The pore-scale method and lattice Boltzmann method are used to simulate the gas and liquid transport inside the microporous layer with different microstructures. The effects of carbon particle diameter,seed rate and volume fraction of polytetrafluoroethylene （PTFE） on gas-liquid transport were studied by comparing effective gas diffusivity and water saturation. The simulation results show that the MPL effective gas diffusivity increases with porosity and carbon particle’s diameter. In contrast,it decreases with the increase of the volume fraction of polytetrafluoroethylene （PTFE） and the seed rate. It is also found that the MPL’s liquid water transport capability increases with particle diameter and the decrease of the seed rate. Moreover,the liquid water transport is the most favorable when the volume fraction of PTFE is 15%. This study provides theoretical support for the optimal design of MPLs.
关键词
质子交换膜燃料电池 /
重构 /
气体扩散 /
水传输 /
微孔层
Key words
proton exchange membrane fuel cells /
reconstruction /
gas diffusion /
liquid transport /
micro-porous layer
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 张拴羊, 杨其国, 徐洪涛, 等. 不同流场结构对PEMFC性能影响的模拟研究[J]. 太阳能学报, 2023, 44(8): 62-67.
ZHANG S Y, YANG Q G, XU H T, et al.Numerical simulation on effect of different flow fields on performance of PEMFC[J]. Acta energiae solaris sinica, 2023, 44(8): 62-67.
[2] XING L, SHI W D, SU H N, et al.Membrane electrode assemblies for PEM fuel cells: a review of functional graded design and optimization[J]. Energy, 2019, 177: 445-464.
[3] GAO Y, HOU Z, WU X Y, et al.The impact of sample size on transport properties of carbon-paper and carbon-cloth GDLs: direct simulation using the lattice Boltzmann model[J]. International journal of heat and mass transfer, 2018, 118: 1325-1339.
[4] 张恒, 詹志刚, 陈奔, 等. 基于XCT的气体扩散层传输特性孔尺度模拟[J]. 太阳能学报, 2023, 44(6): 99-105.
ZHANG H, ZHAN Z G, CHEN B, et al.Pore-scale simulation of gas diffusion layer transport characterics based on XCT[J]. Acta energiae solaris sinica, 2023, 44(6): 99-105.
[5] YANG M Y, JIANG Y Y, LIU J L, et al.Lattice Boltzmann method modeling and experimental study on liquid water characteristics in the gas diffusion layer of proton exchange membrane fuel cells[J]. International journal of hydrogen energy, 2022, 47(18): 10366-10380.
[6] RESHETENKO T, BEN B L.Impact of a gas diffusion layer’s structural and textural properties on oxygen mass transport resistance in the cathode and performance of proton exchange membrane fuel cells[J]. Electrochimica acta, 2021, 371: 137752.
[7] AFRA M, NAZARI M, KAYHANI M H, et al.3D experimental visualization of water flooding in proton exchange membrane fuel cells[J]. Energy, 2019, 175: 967-977.
[8] HOU Y Z, LI X, DU Q, et al.Pore-scale investigation of the effect of micro-porous layer on water transport in proton exchange membrane fuel cell[J]. Journal of the Electrochemical Society, 2020, 167(14): 144504.
[9] BECKER J, WIESER C, FELL S, et al.A multi-scale approach to material modeling of fuel cell diffusion media[J]. International journal of heat and mass transfer, 2011, 54(7/8): 1360-1368.
[10] ZHANG D, CAI Q, GU S.Three-dimensional lattice-Boltzmann model for liquid water transport and oxygen diffusion in cathode of polymer electrolyte membrane fuel cell with electrochemical reaction[J]. Electrochimica acta, 2018, 262: 282-296.
[11] EL HANNACH M, SINGH R, DJILALI N, et al.Micro-porous layer stochastic reconstruction and transport parameter determination[J]. Journal of power sources, 2015, 282: 58-64.
[12] CHEN M Y, DU S J, JUNG J C Y, et al. Effect of dispersion method on ink rheology and microstructure of microporous layer for PEMFCs[J]. Journal of the Electrochemical Society, 2023, 170(5): 054513.
[13] ZHU L J, ZHANG H, XIAO L S, et al.Pore-scale modeling of gas diffusion layers: effects of compression on transport properties[J]. Journal of power sources, 2021, 496: 229822.
[14] ZHU L J, YANG W F, XIAO L S, et al.Stochastically modeled gas diffusion layers: effects of binder and polytetrafluoroethylene on effective gas diffusivity[J]. Journal of the Electrochemical Society, 2021, 168(1): 014514.
[15] SEPE M, SATJARITANUN P, HIRANO S, et al.Investigating liquid water transport in different pore structure of gas diffusion layers for PEMFC using lattice Boltzmann method[J]. Journal of the Electrochemical Society, 2020, 167(10): 104516.
[16] ZHOU C B, GUO L Y, CHEN L, et al.Pore-scale modeling of air-water two phase flow and oxygen transport in gas diffusion layer of proton exchange membrane fuel cell[J]. Energies, 2021, 14(13): 3812.
[17] ZHENG W B, KIM S H.The effects of catalyst layer microstructure and water saturation on the effective diffusivity in PEMFC[J]. Journal of the Electrochemical Society, 2018, 165(7): F468-F478.
[18] HAO L, CHENG P.Capillary pressures in carbon paper gas diffusion layers having hydrophilic and hydrophobic pores[J]. International journal of heat and mass transfer, 2012, 55(1/2/3): 133-139.
[19] HOU Y Z, DENG H, PAN F W, et al.Pore-scale investigation of catalyst layer ingredient and structure effect in proton exchange membrane fuel cell[J]. Applied energy, 2019, 253: 113561.
[20] ANDISHEH-TADBIR M, ORFINO F P, KJEANG E.Three-dimensional phase segregation of micro-porous layers for fuel cells by nano-scale X-ray computed tomography[J]. Journal of power sources, 2016, 310: 61-69.
基金
广东省基础与应用基础研究基金（2022B1515120079）; 国家自然科学基金（52306270）; 广东省基础与应用基础研究基金（2022A1515110456）; 广东省重点邻域研发计划（2019B090909003）
PDF(1978 KB)
