Numerical Investigation of Subcooled Boiling Characteristics of Magnetic Nanofluid under the Effect of Quadrupole Magnetic Field

摘要

This paper investigates numerically the characteristics of subcooled flow boiling of a magnetic nanofluid (refrigerant-113 and 4 vol% Fe3O4) in a vertical annulus, which is exposed to a nonuniform transverse magnetic field generated by the quadrupole magnet. A control volume technique and SIMPLEC algorithm have been used for discretizing the governing equations and pressure-velocity coupling, respectively. The two-fluid model has been used to simulate subcooled flow boiling of the refrigerant-113. The results indicate that subcooled flow boiling characteristics change not only by using nanofluid as the working fluid, but also by applying the nonuniform transverse magnetic field. In the presence of the aforementioned magnetic field due to the Kelvin force, the fluid attracted to the outer wall. This leads to higher bubble detachment frequency so that the heat pumping is increased and the void fraction on the heated wall is decreased. Thus, the critical heat flux as one of the most important parameters in boiling processes will be increased.