Cooling Performances of the Cooling System Using Ferrofluid for High Power IGBT Device

The objective of this study is to numerically investigate the cooling performances of the cooling system using for high power IGBT device with the magnetic field intensities. Methods/Statistical Analysis The governing equations for the ferrofluid are continuity, momentum, energy, Magnetization and Maxwell's equation to analyze the heat transfer characteristics of the ferrofluid in the cavity. The governing equations are calculated by using both GSMAC (generalized simplified maker and cell method) suggested by Kawai and FEM (finite element method). Findings The thermal behaviors of the ferrofluids in the cavity were enhanced with the increase of the magnetic field intensity. The turbulence in the cavity observed apparantely due to the rapid promotion of the heat transfer phenomenon as the magnetic field intensity was increased. The average Nusselt numbers of the ferrofluids with the volume fractions of 4.5 % at H = 5000 A/m, H = 10000 A/m, H = 15000 A/m and H = 20000 A/m increased by 262%, 365%, 394% and 416% than those of H=0 A/m, respectively. The average Nusselt numbers of the ferrofluids with the volume fractions of 6.0 % at H = 5000 A/m increased by 31.0% and 8.0% than those of the volume fractions of 3.0 % and 4.5 %, respectively. In addition, in the case of 20000 A/m magnetic field intensity, the increasing rates showed 11.0% and 2.0% than those of the volume fractions of 3.0 % and 4.5 %, respectively. As a result, the average Nusselt numbers were constantly about 15 maintained after 20000~70000 A/m of the magnetic field intensity. Improvements/Applications The developed cooling system using ferrofluid could be applicable to the micro and miniature high power and heat flux electric and electronic devices required for compactness.