Underhood system consists of various components like Cooler, Fans, Compressor, Engine, Motor, Alternator, Fuel tank, Electrical Unit, etc. Cooler fans should be able to supply sufficient air flow to the various components of Underhood system and maintain the temperature below critical limit. Multiple coolers with heat load applied on it, Engine heat load & Exhaust system heat load makes Underhood system very complex to study. CFD helps in understanding amount of flow rate going to various components, flow pattern inside canopy, identification of flow short circuiting, locating re-circulation & dead regions and thermal distribution inside the Underhood system.