Application of extremum principle of entransy dissipation to battery thermal performance analysis

摘要

In this study, the thermal performance of the hybrid electric bus (HEB) battery compartment is examined according to the principles of heat transfer theory. First, the air flow field in the battery box is numerically analyzed using the computational fluid dynamics(CFD) method. Then, the formation mechanism of flow field is examined to account for the high local temperature, low flow rate, and thermal uneven among the batteries. In addition, the interaction among the batteries, velocity field, and temperature field is explored. According to the extremum principle of entransy dissipation, the configuration of the battery box is adjusted to improve the heat transfer efficiency, with the ultimate goal of enhancing driving security, power performance and fuel economy. Simulation results show that the improved layout of the battery box achieved decrease in entransy dissipation and more uniform temperature among the batteries, verifying the contribution of the extremum principle of entransy dissipation to optimization of heat transfer efficiency in the battery box.