Simulation-Based Development of Thermal Management for Heavy Duty Fuel Cell Commercial Vehicles

Although a promising solution for zero emission long haul transport, a fuel cell system poses a significant challenge when it comes to the thermal management of the system and its integration into a vehicle. This paper discusses the challenges of fuel cell cooling, including low coolant temperature, high losses and large radiators, as well as the challenges of battery thermal management. These difficulties are illustrated using the example of the SeLv project, whose aim is to develop and integrate a fuel cell powertrain for retrofitting of conventional 40t heavy-duty diesel trucks. Firstly, an oversized system and the resulting problems of integrating the components into the vehicle are discussed. To address these challenges, a 1D full vehicle model is developed in Amesim. This simulation model includes the longitudinal dynamics of the vehicle and the characteristics of the powertrain components that define the thermal management requirements. A real, measured driving cycle is used as input data. The radiators and the ambient air flow are modelled in detail, taking into account both the air flow due to vehicle speed and the forced air flow due to the fans. Two different packaging concepts, with the FC cooling system located either behind the cab or in the engine compartment, are evaluated for suitability using the simulation model developed. Furthermore, an attempt is made to identify an optimal thermal system topology through the use of simulation.