To enhance the environmental performance of vehicles, CO2 emission should be reduced and the fuel efficiency should be improved. The fuel efficiency can be improved by reducing the aerodynamic drag of vehicles and improving the thermal efficiency of engines. Further improvement can be achieved by currently developed systems such as the hybrid vehicle (HV), which employs the internal combustion engine and the motor, and by the fuel cell vehicle, which does not require fossil fuel. However, HV and FCHV (Fuel Cell Hybrid Vehicle) have piles of concerns to be tackled such as thermal issues of new devices including the motor, the inverter, the battery and the fuel cell. This paper reviews the thermo-fluid dynamic approaches, which are indispensable to manage these concerns.
