Experimental study of magnetic field effect on bubble lift-off diameter in sub-cooled flow boiling

Abstract

Boiling heat transfer is a process that consist intensive liquid to vapor phase change. Higher heat transfer capacity and lower wall temperatures, which are essential for industrial cooling applications requiring high heat transfer capacities, are vital characteristics of the boiling heat transfer. In spite of tremendous efforts, bubble nucleation and lift-off phenomena in subcooled flow boiling still requires additional studies. Therefore, in this study, the effects of two important parameters including mass flux (85–125kg/m2s) and heat flux (10–40kW/m2) on the bubble lift-off diameter in the isolated bubble regime of subcooled flow boiling are studied in the absence and presence of magnetic field caused by quadrupole magnets. The obtained results indicate that by increase of the heat flux and decrease of the mass flux, the bubble lift-off diameter increases. Besides, in the presence of the magnetic field, changes in bubble lift-off diameter follow the same trend. However, it is evident that in the presence of the magnetic field, bubble lift-off diameter decreases 5–10%.