In the casting of reactive metals,such as titanium alloys,contamination can be prevented if there is no contact between the hot liquid metal and a solid crucible.This can be achieved by containing the liquid metal by means of high frequency AC magnetic field.A water cooled current-carrying coil,surrounding the metal can then provide the required Lorentz forces,and at the same time the current induced in the metal can provide the heating required to melt it.This 'attractive' processing solution has however many problems,the most serious being that of control an containment of the liquid metal envelope,which requires a balance of the gravity and induced inertia forces on the one side,and the containing Lorentz and surface tension forces on the other.To model this process requires a fully coupled dynamic solution of the flow field,magnetic field and heat transfer/melting process to account for.A simplified solution has been published previously(Bhamidipati & El-Kaddah 1991) providing quasi-static solutions only,by taking the irrotational 'magnetic pressure' term of the Lorgentz force into account. The authors remedy this deficiency by modelling the full problem,using CFD techniques.
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