نتایج جستجو برای: pem fuel cell

تعداد نتایج: 1740315  

Journal: :ECS Transactions 2019

2009
Markus Grötsch Michael Mangold Achim Kienle

The connection between PEM fuel cells and common DC-DC converters is examined. The analysis is model-based and done for boost, buck and buck-boost converters. In a first step, the effect of the converter ripples upon the PEM fuel cell is shown. They introduce oscillations in the fuel cell. Their appearance is explained, discussed and possibilities for their suppression are given. After that, th...

Journal: :iranian journal of hydrogen and fuel cell 0
mohammad hossein fili department of mechanical engineering, sari branch, islamic azad university, sari, iran mostafa habibnia department of mechanical engineering, joybay branch, islamic azad university, jouybar, iran peyman ghasemi tamami department of mechanical engineering, tarbiat modares university, tehran, iran

in this study cross section geometry and material of gasket in proton exchange membrane (pem) fuel cells have been investigated to achieve optimized fuel cell in terms of energy efficiency. the role of gaskets in fuel cells is sealing of gas flow channels and preventing from combination of them. in a pem stack, gasket with approved geometry that suffers more stress has better sealing. for this ...

2010
R. A. Silva T. I. Paiva C. M. Rangel

The mechanisms of fuel cell degradation are not well understood. Even though the numbers of installed units around the world continue to increase and dominate the pre-markets, the present lifetime requirements for fuel cells cannot be guarantee, creating the need for a more comprehensive knowledge of material’s ageing mechanism. In this work, failure modes and mechanism of the membrane-electrod...

Maximum Power Point (MPP) tracker has an important role in the performance of fuel cell (FC) systems improvement. Tow parameters which have effect on the Fuel cell output power are temperature and membrane water. So contents make the MPP change by with variations in each parameter. In this paper, a new maximum power point tracking (MPPT) method for Proton Exchange Membrane (PEM) fuel cell is pr...

2003
Brian A. Knight Lei Chen Nancy Garland

The team assembled for this project will perform the following tasks: 1. Obtain representative samples of physical parameter sensors currently available to meet the targets specified in the fuel cells section of the Hydrogen, Fuel Cells and Infrastructure Technologies Program (HFCIT) Multi-Year R,D&D Plan (MYP). 2. Design and construct a facility for testing physical and chemical sensors under ...

2006
Saptarshi Basu Hang Xu Michael W. Renfro Baki M. Cetegen

A fiber optic coupled diode laser sensor has been constructed for in situ measurements of water vapor partial pressure in active proton-exchange membrane (PEM) fuel cell systems. The bipolar plate of a prototypical PEM fuel cell was modified to allow for transmission of a near infrared laser beam through the flow channels on either the fuel or oxidizer side of its membrane-electrode assembly. T...

Ebrahim Afshari, Nasser Baharlou Houreh

An essential requirement for an operating PEM fuel cell is providing proper water content in the membrane. To avoid water flooding an appropriate water balance is required. Here, an analytic model of a planar membrane humidifier for PEM fuel cell is proposed where the effect of dimensional parameters includes membrane thickness, membrane area and channel hydraulic diameter are investigated. A N...

2012
Xiaodong Yang Yongning Liu Sai Li Xiaozhu Wei Li Wang Yuanzhen Chen

Polymer electrolyte membranes (PEM) and Pt-based catalysts are two crucial components which determine the properties and price of fuel cells. Even though, PEM faces problem of fuel crossover in liquid fuel cells such as direct methanol fuel cell (DMFC) and direct borohydride fuel cell (DBFC), which lowers power output greatly. Here, we report a DBFC in which a polymer fiber membrane (PFM) was u...

2009
I. Zamora J. I. San Martín J. J. San Martín V. Aperribay P. Eguía

Usually, modelling of fuel cell systems uses complex expressions, based on the knowledge of physicalchemical phenomena. These models require a good knowledge of the parameters involved in the processes that, in many cases, are difficult to determine. A solution to avoid this difficulty consists in using black-box models, such as those based on artificial neural networks (ANN). This paper presen...

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