A Microscale Modeling Tool for the Design and Optimization of Solid Oxide Fuel Cells
Abstract
:1. Introduction
2. Method
Parameters | Value |
---|---|
Cell temperature, T (°C) | 700 |
Inlet fuel/air pressure, Patm (Pa) | 1.013 × 105 |
Cell output voltage, Vop (V) | 0.7 |
ASL thickness, lASL (μm) | 1,000 |
AFL thickness, lAFL (μm) | 20 |
Electrolyte thickness, lYSZ (μm) | 8 |
CFL thickness, lCSL (μm) | 20 |
CCCL thickness, lCCCL (μm) | 50 |
Porosity, | 0.48 (ASL), 0.23 (AFL), 0.26 (CFL), 0.45 (CCCL) |
Ni volume fraction, | 0.55 (ASL, AFL) |
LSM volume fraction, | 0.475 (CFL), 1 (CCCL) |
Tortuosity, | 3 |
Angle of particle contact, (o) | 30 |
Bruggeman factor, m | 1.5 |
Mean particle diameter, dp (μm) | 1 (ASL, CCCL), 0.5 (AFL, CFL) |
Electrical conductivity of Ni, (s m-1) | |
Electrical conductivity of LSM, (s m-1) | |
Ionic conductivity of YSZ, (s m-1) | |
Diffusion volume of H2, (m3 mol-1) | 7.07 × 10-6 |
Diffusion volume of H2O, (m3 mol-1) | 12.7 × 10-6 |
Diffusion volume of O2, (m3 mol-1) | 16.6 × 10-6 |
Diffusion volume of N2, (m3 mol-1) | 17.9 × 10-6 |
Molar mass of H2, (kg mol-1) | 2 × 10-3 |
Molar mass of H2O, (kg mol-1) | 18 × 10-3 |
Molar mass of O2 , (kg mol-1) | 32 × 10-3 |
Molar mass of N2 , (kg mol-1) | 28 × 10-3 |
Permeability of anode (m2) | 7.93 × 10-16 |
Permeability of cathode (m2) | 3.06 × 10-16 |
Viscosity of fuel (Pa s) | 2.8 × 10-5 |
Viscosity of air (Pa s) | 4 × 10-5 |
Knudsen diffusion coefficient of H2 (m2 s-1) | 4.37 × 10-4 |
Knudsen diffusion coefficient of H2O (m2 s-1) | 1.46 × 10-4 |
Knudsen diffusion coefficient of O2 (m2 s-1) | 7.64 × 10-5 |
Knudsen diffusion coefficient of N2 (m2 s-1) | 8.17 × 10-5 |
2.1. Electrochemical Reactions in AFL and CFL
2.2. Gas Transport in Porous Electrode
2.2.1. Dusty gas model
2.2.2. Governing equations
2.3. Electrical Conduction
2.4. Boundary Conditions (BCs)
Equations | Boundary | ASL/channel interface | AFL/Electrolyte interface | All others | ||||
Fuel transfer | BC Type | H2 molar concentration | H2O molar concentration | H2 inward molar flux | H2O inward molar flux | Insulation/Symmetry | ||
BC | ||||||||
Boundary | CCCL/channel interface | CFL/Electrolyte interface | All others | |||||
Air transfer | BC Type | O2 molar concentration | N2 molar concentration | O2 inward molar flux | N2 inward molar flux | Insulation/Symmetry | ||
BC | 0 |
Equations | Boundary | Rib/CCCL interface | Rib/ASL interface | CFL/Electrolyte interface | AFL/Electrolyte interface | All others |
Electronic transfer | BC Type | Reference potential | Reference potential | Inward current flow | Inward current flow | Electric insulation |
BC | Vcell- | 0 | ||||
Ionic transfer | BC Type | Interior current source | Interior current source | Electric insulation | ||
BC |
2.5. Numerical Method
3. Results and Discussion
3.1. Model Fitting of the Experimental I-V Curve
3.2. Distributions of Physical Quantities in Stack Cell
3.3. Optimization of Geometry Parameters
3.3.1. Optimization of the CCCL thickness
3.3.2. Optimization of the rib width
3.3.3. Optimization of the CFL thickness
3.3.4. Optimization of the AFL thickness
4. Conclusions
Acknowledgements
References and Notes
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Liu, S.; Kong, W.; Lin, Z. A Microscale Modeling Tool for the Design and Optimization of Solid Oxide Fuel Cells. Energies 2009, 2, 427-444. https://doi.org/10.3390/en20200427
Liu S, Kong W, Lin Z. A Microscale Modeling Tool for the Design and Optimization of Solid Oxide Fuel Cells. Energies. 2009; 2(2):427-444. https://doi.org/10.3390/en20200427
Chicago/Turabian StyleLiu, Shixue, Wei Kong, and Zijing Lin. 2009. "A Microscale Modeling Tool for the Design and Optimization of Solid Oxide Fuel Cells" Energies 2, no. 2: 427-444. https://doi.org/10.3390/en20200427