Comparative analyses of recuperator integration in PEMFC air systems

Meeting stringent carbon reduction goals in the commercial transport sector requires the rapid deployment of zero-emission solutions such as hydrogen fuel cell-powered heavy-duty vehicles. While proton exchange membrane fuel cells (PEMFCs) have demonstrated their viability in this context, significant parasitic losses in the air supply subsystem remain a barrier to further gains in overall system efficiency. The integration of a recuperator presents a substantial opportunity for improvement by enhancing expander energy recovery, thus reducing the net power consumption of the air supply system. This study systematically evaluates the impact of recuperator integration on heavy-duty vehicle PEMFC air system performance. Conceptual modeling and multiobjective optimization of two recuperator types—chevron-type plate heat exchanger and plate fin heat exchanger with offset strip fins—have been performed, using the non-dominated sorting genetic algorithm-II, to minimize pressure drop and maximize effectiveness under a predefined volume constraint. A steady-state model of an air system has been assessed under three distinct load conditions, integrating six optimized recuperator designs, along with one off-the-shelf, experimentally tested shell-and-tube unit. The results demonstrate potential for air system efficiency improvement through recuperator integration, particularly under high-pressure operating conditions. Among all evaluated configurations, one of the optimized plate fin heat exchanger designs achieves the greatest reduction in system power consumption, offering up to 5.29 % improvement at full load. Beyond confirming the efficiency benefits of recuperator integration, the findings underline the essential role of system-specific design optimization in realizing the full benefits of such integration.