A numerical simulation is carried out to analyze the cooling air flow field through the radiator and engine compartment. The governing equations for steady two-dimensional, incompressible, turbulent flow are solved with the two-equation k-ε model for turbulence. In the case of engine idling condition, a potential flow analysis is carried out to obtain the boundary conditions for the viscous flow computation, by the assumption of a line sink located at the position of cooling fan. The measurements of velocity profile in the engine compartment and around the front-end of a vehicle are also made to compare with the numerical results. The agreement between the numerical and experimental resuls is fairy good. It is concluded from the present study that a 2-D computation is a fast and efficient tool for predicting the cooling air flow rate through the radiator.