Proton exchange membrane fuel cells enable efficient and environmentally friendly production of electricity from hydrogen and oxygen, with water and heat as by-products. For optimal operation, proper humidification of the inlet gases is crucial, as it improves the proton conductivity of the membrane, among other positive effects. Despite extensive research, the field of physically consistent humidifier models remains underexplored. This thesis extensively presents the theory of humidification methods, the operation of the fuel cell, modelling approaches, and the reduced-dimensionality model of a proton exchange membrane humidifier. An analysis of the response of a 1D+1D physically consistent membrane humidifier model to various boundary conditions in a counter-flow operation mode confirms the high stability of the model across the entire operational matrix in a low-temperature fuel cell system. The model was verified by comparison with known results from the literature and validated using experimental data. The results show that the model has good predictive capability for humidifier operation, as evidenced by a low root mean square deviation value. Additionally, a sensitivity analysis of the calibration parameters using the Fisher Information Matrix method was conducted, revealing that the parameter d_"mem " (membrane thickness) has the highest identifiability, while k_mem (thermal conductivity coefficient of the membrane) and D_"mem" (membrane diffusivity) are less identifiable in the selected data set.
|