Influence Of Proton Exchange Membrane Fuel Cell Characteristic Parameters And Its Sensitivity Analysis

The performance of fuel cells varies greatly under different operating conditions.A reasonable combination of operating parameters can not only prolong the service life of the fuel cell,but also promote the improvement of output efficiency.In this paper,a three-dimensional multi-component transport CFD model coupled with electrochemical calculations is established for cell simulation,and the key parameter combinations(operating pressure,temperature,porosity,cathode and anode relative humidity)are optimized by response surface methodology analysis and using current density as an indicator.Subsequently,the sensitivity of each parameter to the cell output performance and internal gas distribution(mean and standard deviation of current density and oxygen molar concentration)is obtained by calculation.On this basis,the singlephase and two-phase models under the same load and the two-phase models under different loads are compared and analyzed,respectively.First,the paper uses RSM to optimize the simulation results of the single-phase based on the numerical model to obtain the optimal parameter combinations for the parameters under the single-phase model(0.6 V).It can be found that the mean and standard deviation of current density increases when increasing the operating pressure and the relative humidity on both sides,and the temperature increases to produce the opposite result.The porosity has the largest proportional effect on the uniformity of oxygen distribution.Next,the paper develops the model into a two-phase model and performs parameter optimization analysis to obtain the same combination of optimized parameters.After comparing with the single-phase model,it is found that the difference of the optimal parameter combination is mainly reflected in the value of cathode relative humidity,and the rest is closer.The overall trend of the effect of parameter change on current density is the same.The difference lies in the insignificant effect of porosity on the mean value of current density in the single-phase model,while the proportional effect is larger in the two-phase model.Finally,the two-phase models are optimized for 0.3V and 0.9V voltages and compared with the performance at 0.6V.From the parameter combinations,it can be found that the operating pressure and anode relative humidity are closer for voltages from 0.3V to 0.6V,while there is a large change to 0.9V.The temperature,on the other hand,increases first with the voltage and then decreases significantly.As for the parameter sensitivity,the operating pressure and porosity change more with the voltage change,while the rest of the parameters change less and the overall sensitivity itself is smaller.