In metal foam processing nucleated
gas bubbles expand in a heated metal, then the
foam cools and solidifies. In this work we use
Comsol Multiphysics 4.2 to study heat transfer,
growth and movement of hydrogen gas bubbles
in liquid aluminium for a metal foam expanding
in a 2D mold. In the model, the bubble growth is
simulated by using a specific expansion rate,
then the movement of hydrogen gas bubbles in
liquid aluminium is numerically computed by
using the equations of fluid dynamics coupled to
the level set method. In spite of the problem
complexity and the needed simplifications, the
computational model is very well suited to
describe satisfactorily heat transfer, bubble
expansion, interface movement and fluid flow
during the foaming process. Interesting
considerations can be drawn regarding the
temperature field in the system, the influence of
the mold geometry and the resulting expansion
of the metal foam