Minimization of Hot Air Re-circulation in Engine Cooling System

The objective of the project is to study the re-circulation of hot air into the radiator of the engine cooling system in commercial vehicles; to analyze the effects of the same on the performance of the cooling system and to propose one or more solutions to minimize the re-circulation of hot air. It has been proposed to introduce a cowl arrangement ahead of the radiator to prevent the re-circulation of hot air back to the radiator and to direct the airflow to the core of the radiator more effectively.

The 3D model of the cooling system comprising of Radiator, CAC, cowl, fan, engine, front grille and CAB body was constructed. The whole assembly was placed in the virtual wind tunnel domain created in the modeling software. ANSYS ICEM software was used for geometry simplification & meshing and for pre-processing, whereas for solving and post-processing, ANSYS CFX was used. The simulations have been carried out for both the cases, with & without implementing the extra FRONT COWL. Radiator & CAC were modeled with “POROUS MEDIA” technique, which is available in the software. Multiple Reference Frame (MRF) method has been used to simulate the rotation of Fan. In this method, fan speed has been given as input to software. The study is restricted to only airflow and the heat transfer aspect is not considered. The velocity vectors are mapped throughout the wind tunnel domain for both the cases, in which the regions of re-circulation of air were identified. The velocity vectors and stream line plots showed that there is a significant reduction in the re-circulation of air in the case of implementing the Front Cowl.