Browsing by Author "Peng, Rong-Gui"

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Experimental and numerical studies of micro PEM fuel cell
(2011-10-01)
Peng, Rong-Gui
;
Chung, Chen-Chung
;
Chen, Chiun-Hsun
;
機械工程學系
;
Department of Mechanical Engineering
A single micro proton exchange membrane fuel cell (PEMFC) has been produced using Micro-electro-mechanical systems (MEMS) technology with the active area of 2.5 cm(2) and channel depth of about 500 mu m. A theoretical analysis is performed in this study for a novel MEMS-based design of a micro PEMFC. The model consists of the conservation equations of mass, momentum, species and electric current in a fully integrated finite-volume solver using the CFD-ACE+ commercial code. The polarization curves of simulation are well correlated with experimental data. Three-dimensional simulations are carried out to treat prediction and analysis of micro PEMFC temperature, current density and water distributions in two different fuel flow rates (15 cm(3)/min and 40 cm(3)/min). Simulation results show that temperature distribution within the micro PEMFC is affected by water distribution in the membrane and indicate that low and uniform temperature distribution in the membrane at low fuel flow rates leads to increased membrane water distribution and obtains superior micro PEMFC current density distribution under 0.4V operating voltage. Model predictions are well within those known for experimental mechanism phenomena.
Performance Analysis on Planar Micro PDMS Proton Exchange Membrane Fuel Cell Stack
(2011-06-01)
Peng, Rong-Gui
;
Chen, Tang-Yuan
;
Hsu, Yi-Ja
;
Chen, Chiun-Hsun
;
機械工程學系
The objective of this study is to develop a micro proton exchange membrane fuel cell (PEMFC) stack, in which a flow field plate in each cell is made of polydimethyl-siloxane (PDMS) and manufactured by micro-molding technology. A four-cell micro PEMFC stack in series with a volume of 12 cm x 4.5 cm x 1.2 cm is constructed and tested. The active area of a membrane electrode assembly (MEA) is 2 cm x 2 cm in each individual PEMFC, and the platinum loadings at anode and cathode are 0.3 and 0.5 mg/cm(2), respectively. A series of performance experiments were carried out. Experimental parameters included clamping force and fuel supply condition. Durability tests were carried out as well. Experimental results showed that an appropriate clamping torque range should be considered carefully to enhance performance without narrowing down fuel flow channels. Under a torque of 2.0 kgf . cm, peak power density for this stack is 122.5 mW/cm(2) at 2.0 V. Increase in fuel flow rate is not the best way to improve concentration polarization in this air-breathing stack experiment because of limited air supply, and each cell in the same stack has a different performance under the present arrangement. At present, such stack can maintain a stable power output for a long time (up to 14 hours).