No abstract

Thermal management is an important factor in securing the safe and effective operation of a fuel cell vehicle (FCV). A parameterized stack model of a 100 kW proton exchange membrane fuel cell (PEMFC) is constructed by matlab/Simulink to design and asses the thermal management characteristics of a 100 kW full-powered FCV. The cooling components model, with parameters obtained by theoretical calculation based on the cooling requirement, is developed in the commercial solver GT-COOL. A thermal management simulation platform is constructed by coupling the stack model and cooling components. The accuracy of the modeling method for the stack is validated by comparing with the experimental data. The relationship between the operating temperature and output performance of the fuel cell stack is revealed based on the simulation model. The simulation results show that the operating temperature has a considerable influence on stack performance under high-current operation, and the inlet and outlet temperatures of the stack change nearly linearly with the increasing environmental temperature. The heat dissipation potential of the thermal management system under the high-load condition is also verified. The temperatures and coolant flow of core components, including the stack, DC/DC, air compressor, and driving motor, can meet the cooling requirements.

Summary In the past decade, nanofluids have proven effective for heat transfer enhancement of many thermal engineering applications. This is due to their superior thermal performance characteristics compared with conventional coolants. Therefore, the adoption of nanofluids as alternative coolants in proton exchange membrane fuel cell (PEMFC) cooling systems is considered a novel technology and a promising contributor to the solution of thermal management problems that are impeding the commercialization of automotive PEMFC engines. In this article, the thermal performance enhancement of a radiator was experimentally investigated through the addition of Zinc oxide (ZnO) and aluminum nitride (AlN) nanoparticles suspended in a 50/50 mixture of water and ethylene glycol (WEG) as the base fluid for automotive PEMFC cooling systems. The nanofluid concentrations of 0.2 wt% and 0.5 wt% from nanoparticles were used, and the inlet temperature range of the nanofluids was 50°C to 80°C. The experimental results indicate that the heat transfer rate and radiator effectiveness were improved with high flow rates of the base fluid and nanofluid. Furthermore, by increasing the mass concentration of nanoparticles, the heat transfer rate, overall heat transfer coefficient, and radiator effectiveness were enhanced. This can be explained by the significant enhancement of thermal conductivity and Brownian motion benefited from nanofluids. Compared with the base fluid, the heat transfer rate increased by 24.3% and 57.7% at concentrations of 0.2 wt% and 0.5 wt% ZnO nanoparticles, respectively, within the considered temperature range. Meanwhile, the AlN/WEG nanofluids enhancements achieved 15.3% and 30.7% at the same concentrations. In conclusion, the use of ZnO nanoparticles is strongly recommended for suspension in the WEG (50/50 v/v) mixture as a proper coolant for better performance of PEMFC‐based engines.