A phenomenological-based dynamic model for a polymer electrolyte membrane fuel-cell humidifier assembly

Abstract

This paper presents the deduction of a phenomenological-based semi-physical model (PBSM) for the gas humidification in a fuel-cell assembly. Unlike previously published models, the one proposed here includes the momentum transfer effects and their influences over simultaneous heat and mass transfers occurring into the process as a whole. These effects strongly affect the model precision due to the compressible characteristics of the air. High sensitivity of gas properties regarding changes in both pressure and temperature are also included by modelling the gas as a compressible fluid. The model reproduces the air–water vapour mixture behaviour from the compressor discharge to the fuel-cell inlet port. Since the air humidity and temperature conditions must be maintained at their set-points to guarantee an optimal fuel-cell performance, a model such as the one presented here can be used for designing any model-based control strategy towards achieving desirable operative conditions taking also into account the operational context of the considered assembly. The comparative assessment done with experimental data from a real test bench has shown the effectiveness of the proposed model in accurately reproduce the behaviour of such complex systems.Peer ReviewedPostprint (published version