需积分: 37 2.2k 浏览量 更新于2023-05-26 评论 1 收藏 307KB PDF 举报
PCB压合结构厚度解析_20200923 Desigh by Suwin 钟 1.了解基本换算 1oz厚度=1.4mil * 0.0254=0.035mm /1000 = 35um 1mil = 0.0254mm 1mm = 1000um 2.了解常用PP规格 PP ：Homopoly 聚丙烯均聚物 常用的PP型号 厚度（mil） 1080 2.5~3.2 2116 4.4~5.0 7628 7.0~8.5
In Fig. 5 (b1) and (b2), the RH distribution patterns of cathode side follow the air flow field geometry while the anode RH patterns in Fig. 5 (a1) and (a2) are inconsistent with hydrogen flow field but affected by the local water content at cathode side. With the membrane thickness of 18 μm in model geometry and the experimental stack, the excellent water transfer capability of the membrane enhances the consistency of water contents at the two sides of the membrane. As shown in Fig. 5 (c1) and (c2), the inversely phased wavy flow channels of anode and cathode sides interweave periodically with a thin membrane between them for water content exchange. The RH difference between the anode and cathode sides ranges from 10% to 40% which forms periodically variable water content gradient in the membrane. As shown by the RH distributions in xy cross sections, the water content gradient shows opposite to y direction at cathode inlets and along y direction at cathode outlets due to the counter flow operation of hydrogen and air. The maximum RH difference between anode and cathode sides appears around anode inlets and greatly lowers the local current density which will be analyzed in the following parts.
用中文翻译：As is mentioned above, the wavy flow channels with identical phase for anode and cathode sides are studied by literatures with single flow channel models . In this section, the parallel and inverse wavy flow field designs with multiple flow channels are compared to study the interaction effects between the neighbored and intercrossed channels. The detailed water content and heat distributions under 1 A/cm2 for case 2 are shown in Fig. 12 as an example for investigation. Fig. 12 (a1) and (b1) present the different geometries with mesh building for the parallel and inverse wavy flow fields. For comparison, the geometric dimensions of the MEA and flow channels are the same for the two models with identical channel numbers. The gas flow channel numbers are both 5 for anode and cathode while the coolant flow channel number is 6 for each layer. The reactant flow directions are also indicated in the two-dimensional schematic of the overlayered H2 and air flow channels. The RH distributions in gas flow channels are shown in Fig. (a2) and (b2). In the parallel wavy flow field design, each anode channel corresponds to the cathode channel on the other side of the membrane with similar mass transfer processes to those of the single channel model.
- 我的内容管理 收起
- 我的资源 快来上传第一个资源
- 我的收益 登录查看自己的收益
- 我的积分 登录查看自己的积分
- 我的C币 登录后查看C币余额