A Critical Review on Hybrid Nanofluid Applications for Enhanced Thermal Management in Vehicle Radiators

Improving heat dissipation in automotive radiators is critical for enhancing engine performance, fuel efficiency, and emissions control. Conventional coolants often exhibit limited thermal performance, which constrains the ability of heat exchangers to meet growing thermal loads in modern engines. This study explores the use of hybrid nanofluids engineered fluids containing two distinct types of nanoparticles suspended in a base fluid as advanced working media for automobile radiator systems. By combining the complementary thermal properties of different nanoparticles, hybrid nanofluids can achieve higher effective thermal conductivity and convective heat transfer rates compared to traditional coolants. A systematic analysis is conducted to evaluate the thermal and flow behavior of selected hybrid nanofluid formulations under variable coolant flow conditions and particle concentrations. The investigation integrates detailed measurements of heat transfer enhancement, pressure loss, flow stability, and radiator effectiveness. Results demonstrate that optimized hybrid nanofluids significantly enhance convective heat transfer without imposing excessive pumping power penalties. Additionally, practical considerations such as fluid stability and compatibility with radiator materials are discussed. The findings suggest that hybrid nanofluids hold considerable promise for next-generation automotive cooling systems, although challenges related to long-term use, material interactions, and formulation cost remain to be addressed.