论文和技术资料

Here we investigate a promising passive cooling method through making advantage of the unique properties of ferrofluid. When a magnetic dipole or a permanent magnet is put at the hot side of a system, it will attract the cold ferrofluid to the hot place and displace the hot ferrofluid since cold ferrofluid below Tc has much stronger magnetization than that of hot ferrofluid above Tc. Then the hot ferrofluid is compelled to the cold side and transfer heat with heat sink to implement system cooling purpose. This paper includes simulation results of ferrofluid flow and heat transfer under the above mentioned condition. The magnetic field was applied through two methods: (1) a magnetic dipole was assumed at point (0,0), and the magnetic field distribution could be calculated according to the magnetic flux formulas of a magnetic dipole. Then the magnetic force was derived based on the magnetic field distribution. (2) a permanent magnet was simulated instead of a magnetic dipole. All considered problems are based on two-dimensional computational simulation using COMSOL Multiphysics.