introduction: computational methods
TRANSCRIPT
G. Bandlamudi*1, C. Siegel1,2G. Bandlamudi*1, C. Siegel1,2
1 ZBT GmbH, Germany, 2SIEGEL SCHLEIMER INGENIEURS*Corresponding author: ZBT GmbH, Carl-Benz*Corresponding author: ZBT GmbH, Carl-Benz
g.bandlamudi@zbt
Introduction:HT PEMFC modeling and simulation performedHT PEMFC modeling and simulation performed
employing a 24-channel gas supply (300 cm² ofactive area)active area)
• Fuel and oxidant gas velocities in the flow field andthe porous media and their pressure profiles studiedthe porous media and their pressure profiles studied
• The electrochemical behaviour studied usingElectrochemical Impedance Spectroscopy and isElectrochemical Impedance Spectroscopy and iscompared to COMSOL Multiphysics® basedsimulationssimulations
• Optimum operating conditions, based on evencurrent distribution (across the entire active area)current distribution (across the entire active area)and lowest possible pressure drop were identified.
Experimental Measurements:• Experiments performed in a dedicated test stand• HT PEMFC prototype successfully tested• HT PEMFC prototype successfully tested• Modeling parameters identified
Figure 1. Tested HT PEMFC prototype and test stand.Figure 1. Tested HT PEMFC prototype and test stand.
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Figure 2. Recorded performance curves of the HTPEMFC prototype.PEMFC prototype.
Table 1. Electrochemical modeling parameters.
Temp / °K Temp / °C Rct / Ω I0c / A i0c / mA/cm²
433.15 160 0.0146346 1.275198184 4.25
443.15 170 0.0145253 1.314455434 4.38
453.15 180 0.0143954 1.356246001 4.52
463.15 190 0.0140992 1.415296461 4.72
1,2, C. Heßke1 and A. Heinzel11,2, C. Heßke1 and A. Heinzel1
SIEGEL SCHLEIMER INGENIEURS-CONSEILS s.à r.l, LuxembourgBenz-Straße 201, D-47057 Duisburg, Germany,Benz-Straße 201, D-47057 Duisburg, Germany,
Computational Methods:• Complete cell geometry reconstructed• Complete cell geometry reconstructed• Best mesh generated• Solver settings for large-area HT PEMFCs identified:• Solver settings for large-area HT PEMFCs identified:MUMPS direct solver (parametric) and segregatedsolversolver
• Converged results returned
5 layer MEA sandwichedbetween two flow-fields
Cathode inlet areabetween two flow-fields
Inlet cathode
Swept mesh
Outletcathode
Figure 3. 3D geometry and generated mesh.
Results and Conclusion:
Figure 3. 3D geometry and generated mesh.
Results and Conclusion:• Predicted results comparable to the cell's measured
electrochemical performanceelectrochemical performance• Simulations yielded important and necessary
quantities profiles relevant to the manifolds at thequantities profiles relevant to the manifolds at thein-, and outlets of the flow field plate
• Improvements on the manifolds both on the anode• Improvements on the manifolds both on the anodeas well as on the cathode side are planned
• In the next iterations, validation will be performed• In the next iterations, validation will be performedand changes implemented in the model.
0.2311
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Figure 4. Profiles of 1) O2, 2) H2O, 3) Current density,4) Fluid temperature T and 5) Solid temperature T4) Fluid temperature Tf and 5) Solid temperature Ts