A Numerical Approach to Develop the Front End Cooling Package in a Vehicle Using Predicted Engine Fan Performance Data and Vehicle System Resistances

This paper summarizes the numerical development of a cooling package in a vehicle. The radiator and condenser fan performance curves are predicted using Computational Fluid Dynamics (CFD) approach using a numerical AMCA (Air Motion Control Association) chamber. The same procedure is extended to generate the combined fan performance curves. System resistance curves at various vehicle speeds are determined. To determine the vehicle system resistance at various vehicle speeds, a full vehicle CFD model in a numerical wind tunnel is developed and analyzed at different fan speeds.

The changes in radiator flow for different scenarios such as change in fan geometry and the removal of condenser fan are outlined in this work.

The study is then extended to predict radiator hot flow and coolant inlet temperatures at different vehicle load conditions. An analytical method to determine hot air flow and air temperature at radiator exit is developed. This approach is extended to predict coolant inlet temperatures, using the radiator performance data. This can further be used to compute the required change in radiator airflow to meet the coolant inlet temperature targets. The feasibility of removing the condenser fan and still meet the temperature targets is also outlined.