Design and Performance Analysis of a Hybrid Cooling System for Automotive Applications

The increasing power density of modern internal combustion engines and hybrid electric vehicles has placed higher demands on thermal management systems. Conventional air-cooled or liquid-cooled systems alone often struggle to maintain optimal engine operating temperatures under varying load and environmental conditions. This study investigates the design and performance of a hybrid cooling system that combines liquid cooling with supplementary air-cooling mechanisms. A computational fluid dynamics (CFD) model was developed to simulate coolant flow, heat transfer rates, and temperature distribution under multiple driving scenarios. An experimental prototype was also fabricated and tested on a 1.5L four-cylinder engine under varying loads and ambient temperatures. Results showed that the hybrid cooling system reduced maximum cylinder head temperature by 12–15% compared to traditional liquid cooling, while improving fuel efficiency by 3% and lowering NOx emissions. The study concludes that hybrid cooling systems provide a promising approach to enhance thermal efficiency, extend engine life, and support compliance with increasingly stringent emission standards.