Automotive world is rapidly changing driven by the CO2 emission regulations [1], [2] worldwide asking for a dramatic fuel consumption reduction.
The on board thermal management has a relevant role influencing the front vehicle design and sizing to assure the right heat rejection capacity and being crucial to guarantee the on board system efficiency and reliability.
In this context the dual level cooling system with water cooled charge air cooling is a clear trend leading to a new generation of systems [3, 4].
This paper describes a compact solution to effectively implement a dual cooling loop system with water cooled charge air cooler and water cooled condenser on small/subcompact cars giving the opportunity to integrate additional modules (e.g. in case of hybrid powertrain) to the secondary loop.
The system key element is the capacity to manage the whole vehicle heat rejection need with a single layer radiator enabling the redesign of the front end so reducing the aerodynamic drag and making more effective the adoption of active aerodynamics devices (e.g. Active Grid Shutters).
The proposed solution ensures all the advantages of water cooled charge air cooler enabling a further improvement of the air conditioning system thanks to a more effective condensation phase that also leads to noise reduction and lower fuel consumption in real world.
The single layer cooling module has been developed in order to maximize the layout advantages of such a system, integrating on the same radiator both the high and low temperature cooling circuits enabling packaging an weight optimization at vehicle level.
A Fiat 500 0.9L TwinAir 85 HP turbocharged engine vehicle demonstrator has been realized and fully tested.
The system enables to reduce the thermal module thickness of 50 mm guaranteeing the demanded heat rejection and the fuel economy improvement (i.e. −5% on US06 @35°C).
Further improvement can be achieved properly designed the vehicle front end.