Mathematical Modeling of Vehicle Fuel Cell Power System Thermal Management

A mathematical model of vehicle fuel cell system thermal management has been developed to investigate the effects of various design and operating conditions on the thermal management and to understand the underlying mechanism. The fuel cell stack structure is represented by a lumped thermal mass model, which has the heat transfer and pressure loss characteristics of the fuel cell stack structure. The whole thermal management system is discretized into many volumes, where each flowspit is represented by a single volume, and every pipe is divided into one or more volumes. These volumes are connected by boundaries. The model is solved numerically to analyze thermal management system performance.

The effects of coolant flow rates and air flow rates on the system thermal performance, the stack thermal capacity on the transient thermal performance have been investigated in detail. The results indicate that the radiator airside is the key factor to affect the system performance, when the coolant flow rate is enough to deliver the heat from the stack. The stack thermal capacity has great effects on the system transient thermal performance.