Search results

1 – 10 of 41
To view the access options for this content please click here
Article
Publication date: 16 November 2010

Massimo Guarnieri and Federico Moro

The purpose of this paper is to simulate passive proton exchange membrane fuel cells (PEMFCs) for portable electronic devices by means of a non‐linear lumped circuit based…

Abstract

Purpose

The purpose of this paper is to simulate passive proton exchange membrane fuel cells (PEMFCs) for portable electronic devices by means of a non‐linear lumped circuit based on electrical, mass transfer and electro‐kinetic equations.

Design/methodology/approach

Electrical, mass transfer and electro‐kinetic equations are combined in order to derive a non‐linear lumped circuit. The dynamic circuit model is tested in realistic operating conditions.

Findings

An original equivalent circuit model for simulating the transient behavior of passive PEMFCs is proposed. The PEMFC is represented as a non‐linear equivalent circuit with controlled lumped parameters depending on pressure, temperature, hydration, and system capacity.

Research limitations/implications

Lumped parameters are synthesized assuming a one‐dimensional fuel cell model since layer thicknesses are much smaller than other dimensions. Heat generation and transfer are not modeled even though lumped parameters depend on temperature.

Practical implications

The proposed circuit model can be implemented directly in circuit simulators for designing power management units needed to interface small‐passive PEMFCs and portable electronics such as PDAs, laptops, or mobile phones.

Originality/value

The fuel cell is represented as a non‐linear controlled generator whose parameters are derived directly from multiphysics equations rather than empirical relationships. The dynamic behaviour of PEMFCs can be simulated on completely different times scales, i.e. during transients or during the discharge phase.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

To view the access options for this content please click here
Article
Publication date: 2 May 2017

Saeed Reza Allahkaram and Namdar Mohammadi

This paper aims to evaluate corrosion behavior of bare and PbO2-coated stainless steel 316L, as prospective candidates for bipolar plates, in simulated proton exchange…

Abstract

Purpose

This paper aims to evaluate corrosion behavior of bare and PbO2-coated stainless steel 316L, as prospective candidates for bipolar plates, in simulated proton exchange membrane fuel cell’s (PEMFC’s) environment under operating potentials.

Design/methodology/approach

A set of potentiodynamic, as well as potentiostatic, electrochemical experiments was carried out under both anodic and cathodic potentials. Gathered data were analyzed via fast Fourier transform algorithm for further investigation. X-ray diffraction analysis was also used for determining coating characteristics upon completion of electrochemical experiments.

Findings

Results revealed that bare SS316L is a better candidate for bipolar plate material under anodic potential, as it is cathodically protected. However, PbO2-coated SS316L is favorable under cathodic potential, as bare specimen will suffer localized corrosion in the form of pitting.

Research limitations/implications

It would be of interest if all the experiments are carried out in a PEMFC stack.

Practical implications

This research strives to promote the use of electrochemical noise measurement for practical corrosion monitoring of coated bipolar plates in fuel cells.

Social implications

Improving the corrosion resistance of bipolar plates will expedite commercialization of PEMFCs, which in turn will translate into a substantial reduction in carbon footprint.

Originality/value

This research strives to promote the use of electrochemical noise measurement for practical corrosion monitoring of coated bipolar plates in fuel cells.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 2 August 2019

Fupeng Cheng, Jinglong Cui, Shuai Xu, Hongyu Wang, Pengchao Zhang and Juncai Sun

The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton…

Abstract

Purpose

The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange membrane fuel cells (PEMFCs), a protective Nb-modified layer is formed onto stainless steel via the plasma surface diffusion alloying method. The effect of diffusion alloying time on electrochemical behavior and surface conductivity is evaluated.

Design/methodology/approach

In this work, the surface electrical conductivity and corrosion resistance of modified specimen are evaluated by the potentiodynamic and potentionstatic polarization tests. Moreover, the hydrophobicity is also investigated by contact angle measurement.

Findings

The Nb-modified 430 SS treated by 1.5 h (1.5Nb) presented a lower passivation current density, lower interfacial contact resistance and a higher hydrophobicity than other modified specimens. Moreover, the 1.5 Nb specimen presents a smoother surface than other modified specimens after potentionstatic polarization tests.

Originality/value

The effect of diffusion alloying time on electrochemical behavior, surface conductivity and hydrophobicity of modified specimen is evaluated. The probable anti-corrosion mechanism of Nb-modified specimen in simulated acid PEMFC cathode environment is presented.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 5 February 2018

Mahiro Kato, Asegun Henry, Samuel Graham, Duc Hong Doan and Kazuyoshi Fushinobu

This paper aims to investigate the oxygen transport characteristics in the electrolyte membrane of proton exchange membrane fuel cell (PEMFC), in particular, the water…

Abstract

Purpose

This paper aims to investigate the oxygen transport characteristics in the electrolyte membrane of proton exchange membrane fuel cell (PEMFC), in particular, the water content dependence and the microscopic view of the molecular transport.

Design/methodology/approach

Molecular dynamics simulation is used to examine the oxygen transport characteristics in the electrolyte membrane of PEMFC that we have experimentally observed in our previous study.

Findings

Molecular dynamics simulation well predicts the diffusion coefficient of oxygen in the membrane. It was found that the oxygen molecules have preference in their transport passage that governs the property.

Originality/value

First attempt is to theoretically examine the experimentally observed water uptake dependence of the oxygen diffusion coefficient in membrane and to explain the mechanism.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

To view the access options for this content please click here
Article
Publication date: 20 September 2011

A.B. Mahmud Hasan, M.A. Wahab and S.M. Guo

The purpose of this paper is to present the results of analysis of the transport gases and liquid water between the gas diffusion layer (GDL) and gas flow channel (GFC) of…

Abstract

Purpose

The purpose of this paper is to present the results of analysis of the transport gases and liquid water between the gas diffusion layer (GDL) and gas flow channel (GFC) of proton exchange membrane fuel cells (PEMFCs). These results are then used to describe the effects of the GDL‐GFC interfacial conditions on the general performance of PEMFCs.

Design/methodology/approach

This analysis utilizes finite element analysis commercial codes to illustrate the transport of fluids. The gas transport data obtained from the solution are compared with the established works of others. The liquid transport processes are modeled using the Darcy equation coupled with a saturation‐capillary pressure function (the Leverett function) and assuming no phase change. In addition, the boundary conditions for the liquid transport equation are varied in order to show the extent of non‐uniformities at the GDL‐GFC interface.

Findings

Analysis shows that water dispersion from the GDL‐GFC interface extends across the GDL to its other side, and eventually reduces the performance of the PEMFC.

Research limitations/implications

It is well known that CFD simulation of fuel cells is, in general, still facing significant challenges due to the limited understanding of the complex physical and chemical processes existing within the fuel cell. The model is now under further development to improve its capabilities and undergoing further validations.

Practical implications

The simulations can provide detailed information on some of the key fluid dynamics, physical and chemical/electro‐chemical processes that exist in liquid dispersion at the interface of GDL‐GFC in fuel cells which are critical for fuel cell design and optimization.

Originality/value

The simulation can be used to understand liquid dispersion at the interface of GDL‐GFC and provide and alternative to experimental investigations in order to improve the performance of fuel cell.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 21 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

To view the access options for this content please click here
Article
Publication date: 15 June 2011

A. Hasan, S. Guo and M. Wahab

Performance prediction of a proton exchange membrane fuel cell (PEMFC) has been studied using a multiphysics-based numerical simulation. The simulated geometry was a…

Abstract

Performance prediction of a proton exchange membrane fuel cell (PEMFC) has been studied using a multiphysics-based numerical simulation. The simulated geometry was a simple channel, in which the multi species transportation in the porous electrodes and the coupled electrical current and potential distributions were modeled. The 3D simulations provide the cell performance curve and the fuel/oxidant concentration distributions along the feeding channel. To obtain the detailed flow field in the porous gas diffusion layer, a 2D simulation was also performed. The simulations were compared with the available experimental data for a single channel PEMFC and the comparisons are favorable.

Details

World Journal of Engineering, vol. 8 no. 2
Type: Research Article
ISSN: 1708-5284

Keywords

To view the access options for this content please click here
Article
Publication date: 1 April 2004

K.M. El‐Khatib, M.O. Abou Helal, A.A. El‐Moneim and H. Tawfik

This study investigated the corrosion stability of high velocity oxy‐fuel (HVOF) spray SUS316L coatings on aluminium substrate as lightweight bipolar plate materials for…

Abstract

This study investigated the corrosion stability of high velocity oxy‐fuel (HVOF) spray SUS316L coatings on aluminium substrate as lightweight bipolar plate materials for proton exchange membrane fuel cells (PEMFC). Contact resistance, microhardness and structure of the coatings were characterised using a four‐point probe, pneumatic microhardness, XRD and scanning electron microscope techniques. Preliminary electrochemical results indicate that the SUS316L coated plates significantly lowered the corrosion current of the aluminium substrate by more than one order of magnitude. Corrosion stability in relation to the coating thickness is discussed in terms of the structure composition and transpassivity of chromium.

Details

Anti-Corrosion Methods and Materials, vol. 51 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 30 June 2020

Hadi Kashefi, Ahmad Sadegheih, Ali Mostafaeipour and Mohammad Mohammadpour Omran

To design, control and evaluate photovoltaic (PV) systems, an accurate model is required. Accuracy of PV models depends on model parameters. This study aims to use a new…

Abstract

Purpose

To design, control and evaluate photovoltaic (PV) systems, an accurate model is required. Accuracy of PV models depends on model parameters. This study aims to use a new algorithm called improved social spider algorithm (ISSA) to detect model parameters.

Design/methodology/approach

To improve performance of social spider algorithm (SSA), an elimination period is added. In addition, at the beginning of each period, a certain number of the worst solutions are replaced by new solutions in the search space. This allows the particles to find new paths to get the best solution.

Findings

In this paper, ISSA is used to estimate parameters of single-diode and double-diode models. In addition, effect of irradiation and temperature on I–V curves of PV modules is studied. For this purpose, two different modules called multi-crystalline (KC200GT) module and polycrystalline (SW255) are used. It should be noted that to challenge the performance of the proposed algorithm, it has been used to identify the parameters of a type of widely used module of fuel cell called proton exchange membrane fuel cell. Finally, comparing and analyzing of ISSA results with other similar methods shows the superiority of the presented method.

Originality/value

Changes in the spider’s movement process in the SSA toward the desired response have improved the algorithm’s performance. Higher accuracy and convergence rate, skipping local minimums, global search ability and search in a limited space can be mentioned as some advantages of this modified method compared to classic SSA.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0332-1649

Keywords

To view the access options for this content please click here
Article
Publication date: 2 November 2018

David Walwyn, Andreas Bertoldi and Christian Gable

Hydrogen fuel cells could play an important role in meeting the challenges of the Two Degrees Scenario. The purpose of this paper is to review the development of this…

Abstract

Purpose

Hydrogen fuel cells could play an important role in meeting the challenges of the Two Degrees Scenario. The purpose of this paper is to review the development of this technology in South Africa with the aim of understanding how the country can transform its existing socio-technical systems and act to support a hydrogen-based technological innovation system (TIS).

Design/methodology/approach

A mixed methods approach has been followed in this study. Secondary data analysis was used initially to build a profile of South Africa’s present energy system, followed by a stakeholder survey of the emerging hydrogen economy. Respondents were selected based on a convenience/snowball sampling approach and were interviewed using a semi-structured questionnaire, covering opportunities for South Africa in the global hydrogen economy; sources of competitive advantage; the present phase of development; the maturity of each function and the main weaknesses within the TIS; and finally the appropriate policy instrument to remedy the weakness and/or maximise opportunities for local companies.

Findings

The research has shown that the hydrogen economy is still at a pre-competitive level and requires ongoing government support to ensure an energy transition is realised. In particular, it is important that niche experimentation, a proven strategy in respect of successful sustainability transitions, is further pursued. Importantly, the net cost of hydrogen-based transportation, which is still several times larger than the cost of transport based on the internal combustion engine (ICE), must be reduced, especially in the key applications of public transport and underground vehicles. Furthermore, the development of digital technologies to manage supply fluctuations in energy grids must be accelerated.

Originality/value

The South Africa economy will be severely affected by the replacement of the ICEs with battery electric vehicles due to the country’s reliance on ICEs for platinum demand. Fuel cells represent a new market for platinum but the hydrogen TIS is still at a vulnerable point in its development; without policy support, it will not contribute to a successful socio-technical transformation, nor provide an alternative outlet for platinum.

Details

Journal of Manufacturing Technology Management, vol. 30 no. 8
Type: Research Article
ISSN: 1741-038X

Keywords

To view the access options for this content please click here
Article
Publication date: 1 January 2013

Omar Hegazy, Joeri Van Mierlo, Ricardo Barrero, Noshin Omar and Philippe Lataire

The purpose of this paper is to optimize the design and power management control fuel cell/supercapacitor and fuel cell/battery hybrid electric vehicles and to provide a…

Abstract

Purpose

The purpose of this paper is to optimize the design and power management control fuel cell/supercapacitor and fuel cell/battery hybrid electric vehicles and to provide a comparative study between the two configurations.

Design/methodology/approach

In hybrid electric vehicles (HEVs), the power flow control and the powertrain component sizing are strongly related and their design will significantly influence the vehicle performance, cost, efficiency and fuel economy. Hence, it is necessary to assess the power flow management strategy at the powertrain design stage in order to minimize component sizing, cost, and the vehicle fuel consumption for a given driving cycle. In this paper, the PSO algorithm is implemented to optimize the design and the power management control of fuel cell/supercapacitor (FC/SC) and fuel cell/battery (FC/B) HEVs for a given driving cycle. The powertrain and the proposed control strategy are designed and simulated by using MATLAB/Simulink. In addition, a comparative study of fuel cell/supercapacitor and fuel cell/battery HEVs is analyzed and investigated for adequately selecting of the appropriate HEV, which could be used in industrial applications.

Findings

The results have demonstrated that it is possible to significantly improve the hydrogen consumption in fuel cell hybrid electric vehicles (FCHEVs) by applying the PSO approach. Furthermore, by analyzing and comparing the results, the FC/SC HEV has slightly higher fuel economy than the FC/B HEV.

Originality/value

The addition of electrical energy storage such as supercapacitor or battery in fuel cell‐based vehicles has a great potential and a promising approach for future hybrid electric vehicles (HEV). This paper is mainly focused on the optimal design and power management control, which has significant influences on the vehicle performance. Therefore, this study presents a modified control strategy based on PSO algorithm (CSPSO) for optimizing the power sharing between sources and reducing the components sizing. Furthermore, an interleaved multiple‐input power converter (IMIPC) is proposed for fuel cell hybrid electric vehicle to reduce the input current/output voltage ripples and to reduce the size of the passive components with high efficiency compared to conventional boost converter. Meanwhile, the fuel economy is improved. Moreover, a comparative study of FC/SC and FC/B HEVs will be provided to investigate the benefits of hybridization with energy storage system (ESS).

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of 41