| Quasi-three dimensional numerical simulations of characteristics of a single bubble in astirred liquid metal flow field were conducted, with the process of manufacturing aluminumfoam by gas injection into a metal melt as background. The method of Multiple ReferenceFrame and a standard k-εmodel are employed for the computation of three-dimensionalturbulent flows in a cylindrical stirred tank. Bubble movement and deformation are computedin a quasi-three dimensional model simplified from the full three-dimensional model. Tosimulate the bubble behavior under different initial conditions, the VOF method is used fortracking the interface between the two phases, the CSF (Continuum Surface Tension) modelis used for taking the surface tension into account. Computations have been carried out undervarious fluid properties and working parameters to examine their effects. The results revealsome rules of bubble movement and deformation in the stirred melt flow.The calculated results indicate that bubbles generally move along the main streamlines inthe liquid flow field and are prone to be deformed where the velocity increases or pressuredecreases rapidly. Concerning the effects of processing parameters, the followingobservations are found out. As for the rotation speed, the faster the axis rotates the strongerthe bubbles are deformed; while the differences in bubbles' initiate velocities cause littledifferences in bubble motion and deformation. An increase in bubble size, on one hand, leadsto a trend of easier bubble deformation, on the other hand, leads an increase in the forcecaused by the pressure grads. The initiate position of the bubble influences the bubbledeformation directly by deciding which part of the flow will acts on the bubble first. Finallywith increasing surface tension or decreasing inertial force, i.e. with decreasing Webernumber, the bubble becomes more stable. The tendency of bubble deformation is alsowakened with enlarged liquid viscosity.
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