Under-hood CRFM and CAC Air Flow Management of Vehicle to Improve Thermal Performance by 1D method using AMEsim.

Abstract Currently the Automotive industry demands highly competitive product to survive in the global tough competition. The engine cooling system plays a vital role in meeting the stringent emission norms and improving the vehicle fuel economy apart from maintaining the operating temperature of engine. The airflow through vehicle subsystems like the grille, bumper, the heat exchangers, the fan and shroud and engine bay are called as front-end flow. Front end flow (Under-hood air flow) is crucial factor in engine cooling system as well as in determining the aerodynamic drag of vehicle. The airflow through the engine compartment is determined by the front-end vehicle geometry, the CRFM and CAC package and the engine compartment geometry including the inlet and outlet sections. This paper discusses the 1D modelling method and front-end flow rate prediction by 1D method using AMEsim. The required grill opening is decided, and CRFM and CAC specifications are derived. The optimization is done for various vehicle operating condition. From the above iteration the specification of the CRFM and CAC are derived in the early stage of the design. Thus, help in quicker decision and helps to reduce the time and cost in product development. Keywords: Engine cooling system, Front End Flow, Cooling drag, Airflow circuit, Fan, Radiator