Enhancement of Automobile Radiator Performance Using Hybrid Nano Fluids

Resumen

This study presents an experimental performance analysis of an automobile radiator using mono and binary hybrid nanofluids prepared with TiO₂, CuO, and ZnO nanoparticles. The nanoparticles were synthesized and characterized by XRD and TEM, confirming crystalline structures (anatase TiO₂, monoclinic CuO, and hexagonal ZnO) with particle sizes ranging from 25–40 nm. Radiator experiments were conducted as per the DOE framework at varying nanoparticle volume concentration (22–160 g). Among single nanofluids, CuO nanofluid achieved the highest heat transfer rate of 11,938.6 W with an overall heat transfer coefficient of 4006.7 W/m²·K, while TiO₂ nanofluid reached a maximum of 5912.4 W and 865.1 W/m²·K, and ZnO nanofluid attained 3824.7 W and 692.2 W/m²·K, respectively. CuO offered superior thermal conductivity, ZnO shows smoother flow with moderate pressure drop (0.06–0.19 Pa), and TiO₂ ensured excellent suspension stability. To optimize these individual benefits, three binary hybrid nanofluids were prepared: TiO₂–CuO (30:70), CuO–ZnO (74:26), and TiO₂–ZnO (58:42). The hybrid formulations exhibited up to 18–25% higher heat transfer coefficients and 20% improvement in Nusselt number compared to their mono counterparts while maintaining good dispersion stability and acceptable viscosity. These findings suggest that binary hybrid nanofluids can effectively enhance radiator thermal performance, making them promising candidates for next-generation automotive cooling applications.