Abstract
Morphological evolution of particles in semisolid slurries has been modeled as the migration of a double-peak shape solid-liquid interface. The valley between the peaks represents the solute-trapping area between the dendrite arms. Various boundary shear conditions were considered to mimic the real processing environments. A lattice Boltzmann model for isothermal miscible binary flows has been utilized to handle the hydrodynamics and chemical diffusion. Fixed solute concentration at the solid-liquid interface was introduced to simulate the steady growth of the solid particle. Numerical simulations reveal that shearing the slurries in a direction perpendicular to the growth direction of the particle tips encourages dendrite growth, which agrees with the theoretical prediction based on interface stability analysis. Shearing the boundary along a direction parallel to the growth direction of the particle tips, however, caused a larger increment in the migration rate of the interface in the valley, and is considered the major reason for dendrite-rosette morphological transformation.
Original language | English |
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Pages (from-to) | 929-933 |
Number of pages | 4 |
Journal | Computers and Fluids |
Volume | 35 |
Issue number | 8-9 |
DOIs | |
Publication status | Published - 2006 |
Keywords
- fluid dynamics
- liquid solid interface
- dendritic structure
- Semi solid state
- Boltzmann equation
- solidification
- digital simulation
- modelling
- computational fluid dynamics
- lattice model
- mesoscopic systems
- microstructure