Effects of magnetic field on thermo-hydraulic behaviors of magnetic nanofluids in CPU cooling system

This study established a cooling system as high heat dissipation has increasingly become the dominant factor restricting the function of electronic devices, particularly the CPU. The governing parameters of this study are nanoparticle mass percentages (omega = 0.1-0.5%), magnetic field rotation angles (alpha = 0 degrees, 30 degrees, 60 degrees), magnetic field intensity (B = 0.0 T, 0.005 T, 0.010 T, 0.015 T) and Reynolds numbers (Re = 712-1400). Thermal and exergy efficiency and entropy generation are introduced to analyze the comprehensive thermo and hydraulic behaviors of magnetic nanofluids, which is equal to thermoeconomic evaluation. Results indicate that the surface temperature of CPU becomes lower and lower as the increase of magnetic field intensity and rotation angle. The maximum reduction of CPU temperature at B = 0.015 T is 5.6 degrees C compared with that at B = 0 T, and the maximum reduction of CPU temperature at alpha = 60 degrees is 9.5 degrees C compared with that at alpha = 0 degrees. Results also show that the increasing magnetic field intensity and rotation angle are beneficial to improving the exergy efficiency and reducing the entropy generation.