Abstract:A two-dimensional computational model coupling a macroscopic heat and fluid flow analysis with electromagnetic stirring (EMS) in semisolid slurry preparation was developed. The method combining finite element and finite difference was used to deal with coupling electromagnetic field with flow field and temperature field. The characteristics of electromagnetic field, flow field and temperature field under electromagnetic stirring were analyzed, considering the influences of the stirring current and frequency. The dynamic evolution of transport phenomena during solidification under electromagnetic stirring was presented successfully. The simulated results show that a horizontal rotational electromagnetic force with the same rotating direction with the magnetic flux density is uniformly distributed in the stirred melt, but its magnitude decreases from edge to center due to the skin effect of the induced current. The velocity field distribution is similar to the electromagnetic field, but the velocity quickly decreases with the stirring time increasing when the temperature decreases in the melt. The electromagnetic stirring accelerates the solidification rate, and the temperature difference between the melt edge and the melt center becomes small. The altering stirring current and frequency markedly influence the distribution of electromagnetic field, flow field and temperature field.

Key words: electromagnetic stirring; semisolid slurry; electromagnetic field; flow field; temperature field; numerical simulation