In the casting of reactive metals, such astitanium alloys, contamination can be prevented if thereis no contact between the hot liquid metal and a solidcrucible. This can be achieved by containing the liquidmetal by means of high frequency AC magnetic field. Awater cooled current-carrying coil, surrounding themetal can then provide the required Lorentz forces, andat the same time the current induced in the metal canprovide the heating required to melt it. This'attractive' processing solution has however manyproblems, the most serious being that of control ancontainment of the liquid metal envelope, which requiresa balance of the gravity and induced inertia forces onthe one side, and the containing Lorentz and surfacetension forces on the other. To model this processrequires a fully coupled dynamic solution of the flowfield, magnetic field and heat transfer/melting processto account for. A simplified solution has been publishedpreviously (Bhamidipati & El-Kaddah 1991) providingquasi-static solutions only, by taking the irrotational'magnetic pressure' term of the Lorentz force intoaccount. The authors remedy this deficiency by modellingthe full problem, using CFD techniques.
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