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Droplets and aerosolized viral particles expelling from the body through coughing or sneezing and it is spreading to nearby surroundings. Two-phases, three-dimensional, Computational Fluid Dynamics (CFD) model using Reynolds Average Navier Stokes (RANS) equations has been developed to simulate the air flow and the transport and dispersion of the aerosolized viral particles and fine droplets suspended in the air particles through the office. The study presents two cases involving the spreading limits and pathways of the aerosolized viral particles and fine droplets suspended in the air in a place; without and with air conditioning unit. The results showed that the use of air conditioning systems can increase the chances of spreading COVID-19 virus infection. The air-conditioning unit recirculates the same air inside a room, and this has the potential to create a virus-laden environment. Air circulation indoors such as using air conditioning units should be avoided in closed places. Existing ventilation systems should be expanded to include extraction and air filtration systems and/or germicidal, ultraviolet light. Also, opening a window can help bring in fresh air from the outside and disperse stale air inside, and that could help reduce the possibility of the spread of the virus particles in the closed place. Lastly, crowds of people in closed public places should be avoided. This work is beneficial for the ventilation strategy design for mitigating COVID-19. [ABSTRACT FROM AUTHOR]

The vibration of structure are cusecs generation heat on the machine parts, the heat generation dependent onto the natural frequency supplied on the structure and the materials types (mechanical and thermal properties). Therefore, in this paper investigation the heat generation in the beam due to vibration of beam under frequency excitation (harmonic load excitation), for the beam supported with various boundary conditions, simply supported; clamped supported; and cantilever supported beam. Also, the results included evaluated the heat generation as a function of time with different frequency applied of harmonic load, less and more than the natural frequency of beam. The heat generation due to vibration of beam with time is evaluated by analytical investigation and comparison with numerical study, by using finite element method with CFD package program. The results evaluated are shown the generation heat is decreasing with increasing the frequency of the applied harmonic load. In addition to, the value of natural frequency of beam, dependent is effect on the heat generation of vibration beam, therefore, the supported types of beam are effect of the heat generation due to harmonic load, since the natural frequency of beam is dependent on supported types of beam. The comparison of results between analytical investigation and numerical work had shown the good agreement between with maximum error about (1.36%). [ABSTRACT FROM AUTHOR]

Mechanical degradation is often studied in single-cell proton exchange membrane (PEM) fuel cell stack models in assembly process. This however, can increase substantially when moving from assembly process to operation conditions; and also from single-cell to multiple cells. In this study, PEM fuel cell stacks consisting of 1, 3, and 5 cells with an active area of 25 cm² per cell have been simulated in operation mode. Three dimensional non-isothermal solid mechanics-CFD model of a PEM fuel cell stack, integrating the real full scale geometry of all components have been used to study the influence of the number of cells on the stress distribution in a running PEM fuel cell stack. Simulation of a running multi cells stack was successful and has not been previously seen in literatures work. The results showed that the center of the electrode tends to un-displacement. This un-displacement area increases by increasing the clamping torque. The deformations in the stack components during operation were about ten times higher than during assembly process. During assembly process, the increasing in the number of cells increases the total displacement distribution. These status were different during operation, the increasing in the number of cells enhances the uniformity of the total displacement. Increasing the number of cells enhances the uniformity of the mechanical state. The better contact pressure homogeneity was obtained with the greater number of cells and leads to the lower contact resistance. In general, the results showed lower stresses values with lower distributions and more homogeneous and uniformity in the stack that consisting of multi cells. [ABSTRACT FROM AUTHOR]

PEM fuel cell stack assembly process, including clamping pressure, material properties of each component, design (component thickness and cell active area), and number of cells in the stack are important factors influencing the performance and durability of the PEM fuel cell stack. Furthermore, when temperature and relative humidity increase during operation, the membrane absorbs water and swells. Since the relative position between the top and bottom end plates is fixed, the polymer membrane is spatially confined. Thus the GDL will be further compressed under the land and the intrusion into channel becomes more significant. Assembly pressure, contact resistance, membrane swelling and operating conditions, etc., combine to yield an optimum assembly pressure. The clamping pressure is therefore a critical parameter for optimal fuel cell performance and durability. Too high, too low, or inhomogeneous compressions have negative effects on the performance and durability of the stack. In this study, full three-dimensional, non-isothermal computational fluid dynamics (CFD) detailed model of a PEM fuel cell stack has been developed and coupled with a solid mechanics model to simulate the stress distribution inside the stack, which are occurring during fuel cell assembly (bolt assembling), and membrane swelling and cell materials expansion during fuel cell running due to the changes of temperature and relative humidity. The PEM fuel cell stack model simulated includes the following all components in full details; two end-plates, two current plates, two bi-polar plates with straight flow channels for reactants and cooling serpentine water flow channel on the upper face of cathode bi-polar plate, two GDLs, two gaskets, and, an MEA (membrane plus two CLs). The model is shown to be able to understand the many interacting, complex electrochemical, transport phenomena, with stress distribution inside the stack during operation on the performance and durability of the stack that have limited experimental data. Furthermore, the model is shown to be able to provide a computer-aided tool for design and optimize future fuel cell stack with much higher power density, long stack life, and lower cost. [ABSTRACT FROM AUTHOR]

A three-dimensional, multi-phase, non-isothermal computational fluid dynamics model of a proton exchange membrane fuel cell has been used and developed to investigate the hygro and thermal stresses in polymer membrane, which developed during the cell operation due to the changes of temperature and relative humidity. The behaviour of the membrane during operation of a unit cell has been studied and investigated under real cell operating conditions. The results show that the non-uniform distribution of stresses, caused by the temperature gradient in the cell, induces localized bending stresses, which can contribute to delaminating between the membrane and the gas diffusion layers. These stresses in the membrane may explain the occurrence of cracks and pinholes in the membrane under steady-state loading during regular cell operation. The results show that the maximum displacements in membrane for the low, intermediate and high load conditions were 2.58, 2.66, and 2.78 µ m respectively. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive three-dimensional, multi-phase, non-isothermal model of a Proton Exchange Membrane (PEM) fuel cell that incorporates significant physical processes and key parameters affecting the fuel cell performance. The model construction involves equations derivation, boundary conditions setting, and solution algorithm flow chart. Equations in gas flow channels, gas diffusion layers (GDLs), catalyst layers (CLs), and membrane as well as equations governing cell potential and hygro-thermal stresses are described. The algorithm flow chart starts from input of the desired cell current density, initialization, iteration of the equations solution, and finalizations by calculating the cell potential. In order to analyze performance, water and thermal distribution, and mechanical related failure in the cell, the equations are solved using a computational fluid dynamic (CFD) code. Performance analysis includes a performance curve which plots the cell potential (Volt) against nominal current density (A/cm²) as well as losses. Velocity vectors of gas and liquid water, liquid water saturation, and water content profile are calculated. Thermal distribution is then calculated together with hygro-thermal stresses and deformation. The CFD model was executed under boundary conditions of 20°C room temperature, 35% relative humidity, and 1 MPA pressure on the lower surface. Parameters values of membrane electrode assembly (MEA) and other base conditions are selected. A cell with dimension of 1 mm x 1 mm x 50 mm is used as the object of analysis. The nominal current density of 1.4 A/cm² is given as the input of the CFD calculation. The results show that the model represents well the performance curve obtained through experiment. Moreover, it can be concluded that the model can help in understanding complex process in the cell which is hard to be studied experimentally, and also provides computer aided tool for design and optimization of PEM fuel cells to realize higher power density and lower cost. [ABSTRACT FROM AUTHOR]

The aim of this project is to study the influences of the wind flow and dust particles dispersion through Najaf historic city centre. Two phase Computational Fluid Dynamics (CFD) model using a Reynolds Average Navier Stokes (RANS) equations has been used to simulate the wind flow and the transport and dispersion of the dust particles through the historic city centre. This work may provide useful insight to urban designers and planners interested in examining the variation of city breathability as a local dynamic morphological parameter with the local building packing density. [ABSTRACT FROM AUTHOR]

Micro-fuel cells are considered as promising electrochemical power sources in portable electronic devices. The presence of microelectromechanical system (MEMS) technology makes it possible to manufacture the miniaturized fuel cell systems. The majority of research on micro-scale fuel cells is aimed at micro-power applications. Performance of micro-fuel cells are closely related to many factors, such as designs and operating conditions. CFD modeling and simulation for heat and mass transport in micro PEM fuel cells are being used extensively in researches and industrial applications to gain better understanding of the fundamental processes and to optimize the micro fuel cell designs before building a prototype for engineering application. In this research, full three-dimensional, non-isothermal computational fluid dynamics model of a micro proton exchange membrane (PEM) fuel cell with serpentine gas flow channels has been developed. This comprehensive model accounts for the major transport phenomena such as convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields in a micro PEM fuel cell. The model explains many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. [ABSTRACT FROM AUTHOR]

A fuel cell is most interesting new power source because it solves not only the environment problem but also natural resource exhaustion problem. CFD modeling and simulation for heat and mass transport in PEM fuel cells are being used extensively in researches and industrial applications to gain better understanding of the fundamental processes and to optimize fuel cell designs before building a prototype for engineering application. In this research, full three-dimensional, non-isothermal computational fluid dynamics model of a tubular-shaped proton exchange membrane (PEM) fuel cell has been developed. This comprehensive model accounts for the major transport phenomena such as convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields in a tubular-shaped PEM fuel cell. The model explains many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. Three-dimensional results of the species profiles, temperature distribution, potential distribution, and local current density distribution are presented and analysed, with the focus on the physical insight and fundamental understanding. [ABSTRACT FROM AUTHOR]

Durability is one of the most critical remaining issues impeding successful commercialization of broad PEM fuel cell transportation energy applications. Automotive fuel cells are likely to operate with neat hydrogen under load-following or load-levelled modes and be expected to withstand variations in environmental conditions, particularly in the context of temperature and atmospheric composition. In addition, they are also required to survive over the course of their expected operational lifetimes i.e., around 5,500 hrs, while undergoing as many as 30,000 startup/shutdown cycles. The damage mechanisms in a PEM fuel cell are accelerated by mechanical stresses arising during fuel cell assembly (bolt assembling), and the stresses arise during fuel cell running, because it consists of the materials with different thermal expansion and swelling coefficients. Therefore, in order to acquire a complete understanding of the damage mechanisms in the membrane, mechanical response under steady-state hygro-thermal stresses should be studied under real cell operating conditions and in real cell geometry (three-dimensional). In this work, full three-dimensional, non-isothermal computational fluid dynamics model of a PEM fuel cell has been developed to simulate the stresses inside the PEM fuel cell, which are occurring during fuel cell assembly (bolt assembling), and the stresses arise during fuel cell running due to the changes of temperature and relative humidity. A unique feature of the present model is to incorporate the effect of hygro and thermal stresses into actual three-dimensional fuel cell model. In addition, the temperature and humidity dependent material properties are utilize in the simulation for the membrane. The model is shown to be able to understand the many interacting, complex electrochemical, transport phenomena, and stresses distribution that have limited experimental data. This model is used to study and analyse the effect of operating parameters on the mechanical behaviour of PEM. The analysis helped identifying critical parameters and shed insight into the physical mechanisms leading to a fuel cell durability for vehicular applications. [ABSTRACT FROM AUTHOR]

The presence of microelectromechanical system (MEMS) technology makes it possible to manufacture the miniaturized fuel cell systems for application in portable electronic devices. The majority of research on micro-scale fuel cells is aimed at micro-power applications. There are many new miniaturized applications which can only be realized if a higher energy density power source is available compared to button cells and other small batteries. In small-scale applications, the fuel cell should be exceptionally small and have highest energy density. One way to achieve these requirements is to reduce the thickness of the cell (compacted-design) for increasing the volumetric power density of a fuel cell power supply. A novel, simple to construct, air-breathing micro-structured PEM fuel cell which work in still or slowly moving air has been developed. The novel geometry enables optimum air access to the cathode without the need for pumps, fans or similar devices. In addition, the new design can achieve much higher active area to volume ratios, and hence higher volumetric power densities. Three-dimensional, multi-phase, non-isothermal CFD model of this novel design has been developed. This comprehensive model account for the major transport phenomena in an air-breathing micro-structured PEM fuel cell: convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields. The model is shown to understand the many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. Fully three-dimensional results of the species profiles, temperature distribution, potential distribution, and local current density distribution are presented and analyzed with a focus on the physical insight and fundamental understanding. They can provide a solid basis for optimizing the geometry of the PEM micro fuel cell stack running with a passive mode. [ABSTRACT FROM AUTHOR]

Damage mechanisms in a proton exchange membrane fuel cell are accelerated by mechanical stresses arising during fuel cell assembly (bolt assembling), and the stresses arise during fuel cell running, because it consists of the materials with different thermal expansion and swelling coefficients. Therefore, in order to acquire a complete understanding of the mechanical behaviour of the catalyst layers during regular cell operation, mechanical response under steady-state hygro-thermal stresses should be studied under real cell operating conditions and in real cell geometry (three-dimensional). In this work, full three-dimensional, non-isothermal computational fluid dynamics model of a PEM fuel cell has been developed to investigate the behaviour of the cathode and anode catalyst layers during the cell operation. A unique feature of the present model is to incorporate the effect of hygro and thermal stresses into actual three-dimensional fuel cell model. In addition, the temperature and humidity dependent material properties are utilize in the simulation for the membrane. The model is shown to be able to understand the many interacting, complex electrochemical, transport phenomena, and deformation that have limited experimental data. [ABSTRACT FROM AUTHOR]

The presence of microelectromechanical system (MEMS) technology makes it possible to manufacture the miniaturized fuel cell systems for application in portable electronic devices. The majority of research on micro-scale fuel cells is aimed at micro-power applications. There are many new miniaturized applications which can only be realized if a higher energy density power source is available compared to button cells and other small batteries. In small-scale applications, the fuel cell should be exceptionally small and have highest energy density. One way to achieve these requirements is to reduce the thickness of the cell (compacted-design) for increasing the volumetric power density of a fuel cell power supply. A novel, simple to construct, air-breathing micro-structured PEM fuel cell which work in still or slowly moving air has been developed. The novel geometry enables optimum air access to the cathode without the need for pumps, fans or similar devices. In addition, the new design can achieve much higher active area to volume ratios, and hence higher volumetric power densities. Three-dimensional, multi-phase, non-isothermal CFD model of this novel design has been developed. This comprehensive model account for the major transport phenomena in an air-breathing micro-structured PEM fuel cell: convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields. The model is shown to understand the many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. Fully three-dimensional results of the species profiles, temperature distribution, potential distribution, and local current density distribution are presented and analyzed with a focus on the physical insight and fundamental understanding. They can provide a solid basis for optimizing the geometry of the PEM micro fuel cell stack running with a passive mode. [ABSTRACT FROM AUTHOR]

Damage mechanisms in a proton exchange membrane (PEM) fuel cell are accelerated by mechanical stresses arising during fuel cell assembly (bolt assembling), and the stresses arise during fuel cell running, because it consists of the materials with different thermal expansion and swelling coefficients. Therefore, in order to acquire a complete understanding of the damage mechanisms in the membrane and gas diffusion layers, mechanical response under steady-state hygro-thermal stresses should be studied under real cell operating conditions and in real cell geometry (three-dimensional). In this work, full three-dimensional, non-isothermal computational fluid dynamics model of a PEM fuel cell has been developed to simulate the hygro and thermal stresses in PEM fuel cell, which are occurring during the cell operation due to the changes of temperature and relative humidity. A unique feature of the present model is to incorporate the effect of hygro and thermal stresses into actual three-dimensional fuel cell model. The mechanical behaviour of the membrane, catalyst layers, and gas diffusion layers during the operation of a unit cell has been studied and investigated. The model is shown to be able to understand the many interacting, complex electrochemical, transport phenomena, and stresses distribution that have limited experimental data. The results show that the non-uniform distribution of stresses, caused by the temperature gradient in the cell, induces localized bending stresses, which can contribute to delaminating between the membrane and the gas diffusion layers. These results may explain the occurrence of cracks and pinholes in the membrane during regular cell operation. This model is used to study the effect of operating, design, and material parameters on fuel cell hygro-thermal stresses in polymer membrane, catalyst layers, and gas diffusion layers. Detailed analyses of the fuel cell durability under various operating conditions have been conducted and examined. The analysis helped identifying critical parameters and shed insight into the physical mechanisms leading to a fuel cell durability under various operating conditions. Optimization study of a PEM fuel cell durability has been performed. To achieve long cell life, the results show that the cell must be operate at lower cell operating temperature, higher cell operating pressure, higher stoichiometric flow ratio, and must have higher GDL porosity, higher GDL thermal conductivity, higher membrane thermal conductivity, narrower gases channels, thicker gas diffusion layers, and thinner membrane. In these optimum conditions, the maximum deformation (displacement) reduction by about 50% than the base case operating conditions. [ABSTRACT FROM AUTHOR]

The need for improved lifetime of air-breathing proton exchange membrane (PEM) fuel cells for portable applications necessitates that the failure mechanisms be clearly understood and life prediction models be developed, so that new designs can be introduced to improve long-term performance. An operating airbreathing PEM fuel cell has varying local conditions of temperature, humidity. As a result of in the changes in temperature and moisture, the membrane, GDL and bipolar plates will all experience expansion and contraction. Because of the different thermal expansion and swelling coefficients between these materials, hygro-thermal stresses are introduced into the unit cell during operation. In addition, the non-uniform current and reactant flow distributions in the cell result in non-uniform temperature and moisture content of the cell which could in turn, potentially causing localized increases in the stress magnitudes, and this leads to mechanical damage, which can appear as through-the-thickness flaws or pinholes in the membrane, or delaminating between the polymer membrane and gas diffusion layers. Therefore, in order to acquire a complete understanding of these damage mechanisms in the membranes and gas diffusion layers, mechanical response under steady-state hygro-thermal stresses should be studied under real cell operation conditions. A three-dimensional, multi-phase, non-isothermal computational fluid dynamics model of a novel, tubular, ambient air-breathing, proton exchange membrane micro fuel cell has been developed and used to investigate the displacement, deformation, and stresses inside the whole cell, which developed during the cell operation due to the changes of temperature and relative humidity. The behaviour of the fuel cell during operation has been studied and investigated under real cell operating conditions. In addition to the new and complex geometry, a unique feature of the present model is to incorporate the effect of mechanical, hygro and thermal stresses into actual three-dimensional fuel cell model. The results show that the non-uniform distribution of stresses, caused by the temperature gradient in the cell, induces localized bending stresses, which can contribute to delaminating between the membrane and the gas diffusion layers. The non-uniform distribution of stresses can also contribute to delaminating between the gas diffusion layers and the current collectors. These stresses may explain the occurrence of cracks and pinholes in the fuel cells components under steady-state loading during regular cell operation, especially in the high loading conditions. [ABSTRACT FROM AUTHOR]

Abstract: The development of physically representative models that allow reliable simulation of the processes under realistic conditions is essential to the development and optimization of fuel cells, the introduction of cheaper materials and fabrication techniques, and the design and development of novel architectures. Full three-dimensional, multiphase, non-isothermal computational fluid dynamics models of planar air-breathing and airflow-channel PEM fuel cell have been developed. These comprehensive models account for the major transport phenomena in both these types: convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields. The models are shown to understand the many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. Fully three-dimensional results of the species profiles, temperature distribution, potential distribution, and local current density distribution are presented and analyzed with a focus on the physical insight and fundamental understanding for the air-breathing and airflow-channel PEM fuel cells. [Copyright &y& Elsevier]

The development of physically representative models that allow reliable simulation of the processes under realistic conditions is essential for the development and optimization of fuel cells, the introduction of cheaper materials and fabrication techniques, and the design and development of novel architectures. A three-dimensional, multi-phase, non-isothermal computational fluid dynamics model of a novel, simple to construct, tubular, proton exchange membrane (PEM) fuel cell which works in still or slowly moving air has been developed. The novel tubular geometry enables optimum air access to the cathode without the need for pumps, fans, or similar devices. This comprehensive model accounts for the major transport phenomena such as convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields in a tubular-shaped air-breathing PEM fuel cell. The model explains many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally. Three-dimensional results of the species profiles, temperature distribution, potential distribution, and local current density distribution are presented and analysed, with the focus on the physical insight and fundamental understanding. These results provide a solid basis for optimizing the geometry of the PEM fuel cell stack running in a passive mode. [ABSTRACT FROM AUTHOR]

A full three-dimensional, non-isothermal computational fluid dynamics model of a proton exchange membrane (PEM) fuel cell with straight flow field channels has been developed. This comprehensive model accounts for the major transport phenomena in a PEM fuel cell: convective and diffusive heat and mass transfer, electrode kinetics, and potential fields. The feature of the algorithm developed in this work is its capability for accurate calculation of the local activation overpotentials, which in turn results in improved prediction of the local current density distribution. Fully three-dimensional results of the velocity flow field, species profiles, temperature distribution, potential distribution, and local current density distribution are presented. The model is shown to be able to understand the many interacting, complex electrochemical and transport phenomena that cannot be studied experimentally. [ABSTRACT FROM AUTHOR]

The current paper presents the results of a parametric study conducted with a previously described three-dimensional, non-isothermal computational fluid dynamics model of a proton exchange membrane fuel cell, which was developed and discussed in detail in part 1 of this series. The effects of several operating, design, and material parameters on fuel cell performance has been investigated in detail. The results of the current study helped identifying critical parameters and shed insight into the physical mechanisms leading to a fuel cell performance under various operating conditions. Furthermore, the current study demonstrates the use of a comprehensive three-dimensional single-phase model as a design and optimization tool. [ABSTRACT FROM AUTHOR]

A three-dimensional, multi-phase, non-isothermal computational fluid dynamics model of a proton exchange membrane fuel cell has been developed to simulate the hygro and thermal stresses in polymer membrane, which developed during the cell operation. The behaviour of the membrane during the operation of a unit cell has been studied and investigated. The model accounts for both gas and liquid phase in the same computational domain, and thus allows for the implementation of phase change inside the gas diffusion layers. The model includes the transport of gaseous species, liquid water, protons, energy, and water dissolved in the ion-conducting polymer. The new feature of the present model is to incorporate the effect of hygro and thermal stresses into actual three-dimensional, multi-phase, non-isothermal fuel cell model. In addition to hygro—thermal stresses, the model features an algorithm that allows for a more realistic representation of the local activation overpotentials, which leads to improved prediction of the local current density distribution in high accuracy, and therefore, high accuracy prediction of temperature distribution in the cell and then thermal stresses. This model also takes into account convection and diffusion of different species in the channels as well as in the porous gas diffusion layer, heat transfer in the solids as well as in the gases, and electrochemical reactions. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive three-dimensional, multiphase, non-isothermal model of a Proton Exchange Membrane (PEM) fuel cell that incorporates significant physical processes and key parameters affecting the fuel cell performance. The model construction involves equations derivation, boundary conditions setting, and solution algorithm flow chart. Equations in gas flow channels, gas diffusion layers (GDLs), catalyst layers (CLs), and membrane as well as equations governing cell potential and hygrothermal stresses are described. The algorithm flow chart starts from input of the desired cell current density, initialization, iteration of the equations solution, and finalizations by calculating the cell potential. In order to analyze performance, water and thermal distribution, and mechanical related failure in the cell, the equations are solved using a computational fluid dynamic (CFD) code. Performance analysis includes a performance curve which plots the cell potential (Volt) against nominal current density (A/cm²) as well as losses. Velocity vectors of gas and liquid water, liquid water saturation, and water content profile are calculated. Thermal distribution is then calculated together with hygro-thermal stresses and deformation. The CFD model was executed under boundary conditions of 20°C room temperature, 35% relative humidity, and 1 MPA pressure on the lower surface. Parameters values of membrane electrode assembly (MEA) and other base conditions are selected. A cell with dimension of 1 mm x 1 mm x 50 mm is used as the object of analysis. The nominal current density of 1.4 A/cm² is given as the input of the CFD calculation. The results show that the model represents well the performance curve obtained through experiment. Moreover, it can be concluded that the model can help in understanding complex process in the cell which is hard to be studied experimentally, and also provides computer aided tool for design and optimization of PEM fuel cells to realize higher power density and lower cost. [ABSTRACT FROM AUTHOR]