Optimization of Flow Channel Design and Operating Parameters on Proton Exchange Membrane Fuel Cell Using MATLAB

Operating parameters like pressure, temperature, the stoichiometric ratio of reactants, relative humidity and design parameters like rib width to channel width (L:C), the shape of the flow channel and the number of passes on the flow channel are influencing the performance of the Proton Exchange Membrane Fuel Cell (PEMFC). In this paper, optimization of operating and design parameters such as pressure, temperature, inlet reactant mass flow rate and various rib width to channel width (L:C) 1:1, 1:2, 2:1 and 2:2 on serpentine and interdigitated flow channel of 25cm2 active area of the PEMFC was considered. Creo Parametric 1.0 and CFD Fluent 14.0 software packages were used to create the 3 Dimensional (3- D) model and simulation of PEMFC. The optimization was carried out on the various parameters with MINITAB 17 software and MATLAB software. From the first stage, the Landing to channel width (L: C) - 1:1 of serpentine and the interdigitated flow channel has the maximum influence on fuel cell performance and square of response factor (R2) was achieved from the Taguchi method by MINITAB 17 software as 99.48 and 99.71 % respectively. In the second stage, the regression equation or mathematical model obtained from MINITAB 17 software were fed into the MATLAB software to get optimized parameters. Further the power densities were obtained corresponding to the optimized parameters using the CFD Fluent 14.0 software

Parametric Analysis of Proton Exchange Membrane Fuel Cell (PEMFC) Performed by the Taguchi Method

The proton exchange membrane fuel cell (PEMFC) performance depends on the design parameters like landing-to-channel width ratio (L:C), channel depth, shape and number of passes on the flow channel, and operating parameters like temperature, pressure, the stoichiometric ratio of reactants, relative humidity, back pressure on the anode, and cathode flow channels. In this paper, optimization of design and operating parameters such as various landing -to-channel width ratios (L:C -1:1, 1:2, 2:1, and 2:2) of the interdigitated flow channel, pressure, temperature, and the anode and cathode inlet reactant masses on the 25cm^2 electrode surface active area of the PEMFC was carried out. A three dimensional (3-D) PEMFC model was created by Creo Parametric 1.0, meshed by ICEM 14.0 and simulated using the CFD Fluent 14.0 software packages. The optimization of the design and operating parameters was carried out in two stages using Minitab 17 with a standard orthogonal array of the Taguchi method. From the first stage of analysis, it was inferred that the landing-to-channel width ratio (L:C - 1:1) has the biggest influence on the PEMFC performance and the square of response factor (R^2) was achieved by the Taguchi method at 97.95%. In the second stage of analysis, fine-tuned optimization was performed on selected factors which cause an increase in power density of 0.81. Also, R^2 was achieved at 100 % and the results were also validated using the CFD Fluent 14.0 software packages

Interdigitated Flow Channel on a Proton Exchange Membrane Fuel Cell Investigated Using the Response Surface Methodology

Performance of the proton exchange membrane (PEM) fuel cell depends on the operating pressure, operating temperature, stoichiometric ratio of reactant gases, relative humidity, and rib width-to-channel width ratio (R:C), shape of the flow channel, and the number of passes on the flow channel. The effect of pressure, temperature, inlet reactant mass flow rate and rib width-to-channel width ratios of 1:1, 1:2, 2:1, and 2:2 on the power density of a PEM fuel cell with interdigitated flow channel of 25 cm^2 active area of was considered in this study. The response surface methodology was used for optimizing the four above mentioned parameters to find the optimum power density of the PEM fuel cell. The analysis of variance (ANOVA) was used to find the contribution of each parameter to the performance of the PEM fuel cell. Further, numerical results were compared with the experimental validation of the PEM fuel cell. Numerical results of power densities of interdigitated flow channel with R:C ratios of 1:1, 1:2, 2:1, and 2:2 were found to be 0.272, 0.292, 0.267, and 0.281 W/cm^2 and the corresponding experimental results of power density were 0.261, 0.266, 0.254, and 0.264 W/cm^2, respectively

Studies on anode mass composition and cathode flow field design for small-scale to large-scale direct methanol fuel cell stack systems

In this research, the performance studies of a single cell Direct Methanol Fuel Cell with three different mass compositions (20%, 40%, and 60%) of platinum at anode infused in NiTiO3/C and multiple cathode flow fields, such as serpentine, parallel, and sinuous, with 25 cm2 active area. 40% platinum mass composition has been reported with a maximum power density of 24.42 mW/cm2, which is 26.8% and 10.4% higher than the performance observed in 20% and 60% platinum mass composition, respectively, on serpentine flow field. Among the various cathode flow fields, sinuous flow field provided the maximum power density of 28.69 mW/cm2, which is 17.48% and 53.83% higher in performance than that of serpentine and parallel flow fields, respectively. The best-performing catalyst mass composition and flow field, viz., 40% mass composition and sinuous flow field are scaled up to a 100 cm2 active area, and the results showed 16% lower performance compared to a 25 cm2 active area. A three-cell stack is fabricated with the best performing combination with the 100 cm2 active area that delivered a peak power output of 5.8 W, which resulted in 19.4% lower performance than 100 cm2. The stack was tested for stability for 48 h at constant voltage mode and was found that 0.002 W deviation for the entire period

Scaling up Studies on PEMFC Using a Modified Serpentine Flow Field Incorporating Porous Sponge Inserts to Observe Water Molecules

Flooding of the cathode flow channel is a major hindrance in achieving maximum performance from Proton Exchange Membrane Fuel Cells (PEMFC) during the scaling up process. Water accumulated between the interface region of Gas Diffusion Layer (GDL) and rib of the cathode flow field can be removed by the use of Porous Sponge Inserts (PSI) on the ribs. In the present work, the experimental investigations are carried out on PEMFC for the various reaction areas, namely 25, 50 and 100 cm2. Stoichiometry value of 2 is maintained for all experiments to avoid variations in power density obtained due to differences in fuel utilization. The experiments include two flow fields, namely Serpentine Flow Field (SFF) and Modified Serpentine with Staggered provisions of 4 mm PSI (4 mm × 2 mm × 2 mm) Flow Field (MSSFF). The peak power densities obtained on MSSFF are 0.420 W/cm2, 0.298 W/cm2 and 0.232 W/cm2 compared to SFF which yields 0.242 W/cm2, 0.213 W/cm2 and 0.171 W/cm2 for reaction areas of 25, 50 and 100 cm2 respectively. Further, the reliability of experimental results is verified for SFF and MSSFF on 25 cm2 PEMFC by using Electrochemical Impedance Spectroscopy (EIS). The use of 4 mm PSI is found to improve the performance of PEMFC through the better water management

Performance Studies of Proton Exchange Membrane Fuel Cells with Different Flow Field Designs – Review

Proton Exchange Membrane Fuel Cell (PEMFC) is majorly used for power generation without producing any emission. In PEMFC, the water generated in the cathode heavily affects the performance of fuel cell which needs better water management. The flow channel designs, dimensions, shape and size of the rib/channel, effective area of the flow channel and material properties are considered for better water management and performance enhancement of the PEMFC in addition to the inlet reactant's mass flow rate, flow directions, relative humidity, pressure and temperature. With the purpose of increasing the output energy of the fuel cell, many flow field designs are being developed continuously. In this paper, the performance of various conventional, modified, hybrid and new flow field designs of the PEMFC is studied in detail. Further the effects of channel tapering, channel bending, landing to channels width ratios, channel cross-sections and insertion of baffles/blockages/pin-fins/inserts are reviewed. The power density of the flow field designs, the physical parameters like active area, dimensions of channel/rib, number of channels; and the operating parameters like temperature and pressure are also tabulated

Fuel Cell Products for Sustainable Transportation and Stationary Power Generation: Review on Market Perspective

The present day energy supply scenario is unsustainable and the transition towards a more environmentally friendly energy supply system of the future is inevitable. Hydrogen is a potential fuel that is capable of assisting with this transition. Certain technological advancements and design challenges associated with hydrogen generation and fuel cell technologies are discussed in this review. The commercialization of hydrogen-based technologies is closely associated with the development of the fuel cell industry. The evolution of fuel cell electric vehicles and fuel cell-based stationary power generation products in the market are discussed. Furthermore, the opportunities and threats associated with the market diffusion of these products, certain policy implications, and roadmaps of major economies associated with this hydrogen transition are discussed in this review

Natural History of Liver Disease in a Large International Cohort of Children with Alagille syndrome:Results from The GALA Study

BACKGROUND: Alagille syndrome (ALGS) is a multisystem disorder, characterized by cholestasis. Existing outcome data are largely derived from tertiary centers and real-world data are lacking. This study aimed to elucidate the natural history of liver disease in a contemporary, international, cohort of children with ALGS.METHODS: Multicenter retrospective study of children with a clinically and/or genetically confirmed ALGS diagnosis, born Jan-1997 - Aug-2019. Native liver survival (NLS) and event-free survival rates were assessed. Cox models were constructed to identify early biochemical predictors of clinically evident portal hypertension (CEPH) and NLS.RESULTS: 1433 children (57% male) from 67 centers in 29 countries were included. 10 and 18-years NLS rates were 54.4% and 40.3%. By 10 and 18-years, 51.5% and 66.0% of ALGS children experienced ≥1 adverse liver-related event (CEPH, transplant or death). Children (&gt;6 and ≤12 months) with median total bilirubin (TB) levels between ≥5.0 and &lt;10.0 mg/dL had a 4.1-fold (95% CI 1.6 - 10.8) and those ≥10.0 mg/dL had an 8.0-fold (95% CI 3.4 - 18.4) increased risk of developing CEPH compared with those &lt;5.0 mg/dL. Median TB levels between ≥5.0 and &lt;10.0 mg/dL and &gt;10.0 mg/dL were associated with a 4.8 (95% CI 2.4 - 9.7) and 15.6 (95% CI 8.7 - 28.2) increased risk of transplantation relative to &lt;5.0 mg/dL. Median TB &lt;5.0 mg/dL were associated with higher NLS rates relative to ≥5.0 mg/dL, with 79% reaching adulthood with native liver (p&lt;0.001).CONCLUSIONS: In this large international cohort of ALGS, only 40.3% of children reach adulthood with their native liver. A TB &lt;5.0 mg/dL between 6-and-12-months of age is associated with better hepatic outcomes. These thresholds provide clinicians with an objective tool to assist with clinical decision-making and in the evaluation of novel therapies.</p