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Microchannel flow fields for polymer electrolyte fuel cells
Fuel cell technology represents an efficient and relatively quiet way of generating electricity. Among the various types of fuel cells, the polymer electrolyte fuel cell (PEFC) is the leading candidate for portable, automotive and more recently stationary applications. One of the key challenges affe...
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| Format: | Thesis |
| Language: | English |
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Department of Chemical Engineering
2015
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| _version_ | 1867613243493580800 |
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| access_status_str | Open Access |
| author | Chivengwa, Tapiwa |
| author2 | Hussain, Nabeel |
| author_browse | Chivengwa, Tapiwa Hussain, Nabeel |
| author_facet | Hussain, Nabeel Chivengwa, Tapiwa |
| author_sort | Chivengwa, Tapiwa |
| collection | Thesis |
| description | Fuel cell technology represents an efficient and relatively quiet way of generating electricity. Among the various types of fuel cells, the polymer electrolyte fuel cell (PEFC) is the leading candidate for portable, automotive and more recently stationary applications. One of the key challenges affecting both the performance and durability of low temperature PEFCs is water management. Various water management strategies in PEFCs have been employed to date ranging from manipulation of operating conditions, fuel cell component design and flow field design to name a few. The optimisation of the flow field design for water removal has primarily focused on the use of flow channels which are in the minichannel range. This study investigated the use of a microchannel flow field design (channel hydraulic diameters of less than or equal to 200 ìm) for a low temperature PEFC. Specifically it focused on the effect of using a microchannel design on overall fuel cell performance, pressure drop and the cell voltage behaviour over time. In addition the effect of different operating conditions was also investigated. The overall aim was to develop a more comprehensive understanding of the use of a microchannel based flow field system with specific focus on water management. Fuel cell testing of two different flow field designs, namely a microchannel design and a more conventional commercial minichannel design, was performed in a single cell set up. Two operating conditions, cathode flow rate and cell compression, were varied and the effect on overall fuel cell performance and limiting current was investigated. Several diagnostic measurements including polarization curve, high frequency resistance, electrochemical impedance spectroscopy, pressure drop co-efficient and cell voltage monitoring were conducted to understand the water management behaviour and trends in the two different aforementioned flow field designs. |
| format | Thesis |
| id | oai:open.uct.ac.za:11427/13674 |
| institution | University of Cape Town (South Africa) |
| language | eng |
| last_indexed | 2026-06-10T12:33:01.081Z |
| license_str | Not specified — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository |
| publishDate | 2015 |
| publishDateRange | 2015 |
| publishDateSort | 2015 |
| publisher | Department of Chemical Engineering |
| publisherStr | Department of Chemical Engineering |
| record_format | dspace |
| source_str | UCTD — University of Cape Town Open Access Repository |
| spelling | oai:open.uct.ac.za:11427/13674 Microchannel flow fields for polymer electrolyte fuel cells Chivengwa, Tapiwa Hussain, Nabeel Chemical Engineering Fuel cell technology represents an efficient and relatively quiet way of generating electricity. Among the various types of fuel cells, the polymer electrolyte fuel cell (PEFC) is the leading candidate for portable, automotive and more recently stationary applications. One of the key challenges affecting both the performance and durability of low temperature PEFCs is water management. Various water management strategies in PEFCs have been employed to date ranging from manipulation of operating conditions, fuel cell component design and flow field design to name a few. The optimisation of the flow field design for water removal has primarily focused on the use of flow channels which are in the minichannel range. This study investigated the use of a microchannel flow field design (channel hydraulic diameters of less than or equal to 200 ìm) for a low temperature PEFC. Specifically it focused on the effect of using a microchannel design on overall fuel cell performance, pressure drop and the cell voltage behaviour over time. In addition the effect of different operating conditions was also investigated. The overall aim was to develop a more comprehensive understanding of the use of a microchannel based flow field system with specific focus on water management. Fuel cell testing of two different flow field designs, namely a microchannel design and a more conventional commercial minichannel design, was performed in a single cell set up. Two operating conditions, cathode flow rate and cell compression, were varied and the effect on overall fuel cell performance and limiting current was investigated. Several diagnostic measurements including polarization curve, high frequency resistance, electrochemical impedance spectroscopy, pressure drop co-efficient and cell voltage monitoring were conducted to understand the water management behaviour and trends in the two different aforementioned flow field designs. 2015-08-10T06:42:51Z 2015-08-10T06:42:51Z 2015 Master Thesis Masters MSc (Eng) http://hdl.handle.net/11427/13674 eng application/pdf Department of Chemical Engineering Faculty of Engineering and the Built Environment University of Cape Town |
| spellingShingle | Chemical Engineering Chivengwa, Tapiwa Microchannel flow fields for polymer electrolyte fuel cells |
| thesis_degree_str | Master's |
| title | Microchannel flow fields for polymer electrolyte fuel cells |
| title_full | Microchannel flow fields for polymer electrolyte fuel cells |
| title_fullStr | Microchannel flow fields for polymer electrolyte fuel cells |
| title_full_unstemmed | Microchannel flow fields for polymer electrolyte fuel cells |
| title_short | Microchannel flow fields for polymer electrolyte fuel cells |
| title_sort | microchannel flow fields for polymer electrolyte fuel cells |
| topic | Chemical Engineering |
| url | http://hdl.handle.net/11427/13674 |
| work_keys_str_mv | AT chivengwatapiwa microchannelflowfieldsforpolymerelectrolytefuelcells |