Show simple item record

dc.contributor.authorOhn, Heebong
dc.date.accessioned2021-10-08T19:22:52Z
dc.date.available2021-10-08T19:22:52Z
dc.date.issued2007-08-31
dc.identifier.urihttp://hdl.handle.net/1808/32076
dc.descriptionThesis (M.S.)--University of Kansas, Chemical & Petroleum Engineering, 2007.en_US
dc.description.abstractA capillary pressure curve is used to account for the mass transport limitation in the porous gas diffusion layer (GDL) in modeling two-phase transport phenomena in a fuel cell. Various assumptions and approximations on capillary pressure curve have been made to develop models due to the scarcity of the experimental data of gas diffusion layers (GDL). The lack of experimental data of capillary pressure versus liquid water saturation level hinders progress in model validation. Capillary pressure versus saturation curves for imbibition (liquid water displaces air) and drainage of a nonwetting phase (water) were measured for SGL SIGRACET® and Toray TGPH060 gas diffusion materials. The volume displacement method and neutron imaging technique were employed to measure capillary pressure curves for gas diffusion materials. The experimental results showed that 30wt% wet-proofed carbon paper displayed lower water saturation at the same capillary pressure compared to that of 10wt% and 20wt% wet-proofed carbon papers. No significant capillary pressure hysteresis was observed due to the hydrophobic material coated on the gas diffusion material. The capillary pressure curve of microporous layer showed higher water saturation level which could be attributed to water penetrated through the cracks on the surface of the microporous layer. Due to the similar structure of the gas diffusion material, capillary pressure curves could be correlated to a single Leverett function. It is believed that the liquid water only transports through the hydrophilic pores generating air/water/carbon system. Neutron imaging technique is used to measure the capillary pressure curve in in-plane direction due to the limited resolution of the current detector system. The results showed that water does not imbibe spontaneously into 0wt% wet-proofed carbon paper because of the pore structure on the surface. The catalyst layer imbibes water spontaneously which shows that when a fuel cell is operated at flooding condition catalyst layer can be readily flooded due to its hydrophilic property.en_US
dc.publisherUniversity of Kansasen_US
dc.rightsThis item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author.en_US
dc.subjectApplied sciencesen_US
dc.subjectCapillary pressureen_US
dc.subjectGas diffusion materialen_US
dc.subjectPEM fuel cellen_US
dc.titleMeasurement of capillary pressure properties of gas diffusion materials used in proton exchange membrane fuel cellsen_US
dc.typeThesisen_US
dc.thesis.degreeDisciplineChemical & Petroleum Engineering
dc.thesis.degreeLevelM.S.
kusw.bibid6599326
dc.rights.accessrightsopenAccessen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record