Cross-Permeability of the Semisolid Region in Directional Solidification: A Combined Phase-Field and Lattice-Boltzmann Simulation Approach
- Resource Type
- Authors
- N. Giesselmann; C. Haberstroh; B. Böttger
- Source
- JOM. 68:27-36
- Subject
- 010302 applied physics
Materials science
Field (physics)
General Engineering
Mechanical engineering
02 engineering and technology
Mechanics
021001 nanoscience & nanotechnology
01 natural sciences
Dendrite (crystal)
Permeability (earth sciences)
Flow velocity
Phase (matter)
0103 physical sciences
Fluid dynamics
Perpendicular
General Materials Science
0210 nano-technology
Directional solidification
- Language
- ISSN
- 1543-1851
1047-4838
Based on the results of microstructure simulations, fluid flow through the semisolid region during directional solidification of the technical Ni-base alloy 718 has been studied. Three-dimensional microstructures at different positions in the semisolid region were obtained by using a multicomponent multiphase-field model that was online coupled to a commercial thermodynamic database. For the range of five different primary dendrite distances λ 1 between 50 µm and 250 µm, the flow velocity and the permeability perpendicular to the dendrite growth direction was evaluated by using a proprietary Lattice-Boltzmann model. The commercial CFD software ANSYS FLUENT was alternatively applied for reference. Consistent values of the average flow velocity along the dendrites were obtained for both methods. From the results of the fluid flow simulations, the cross-permeability was evaluated as a function of temperature and fraction liquid for each of the five different primary dendrite distances λ 1. The obtained permeability values can be approximated by a single analytical function of the fraction liquid and λ 1 and are discussed and compared with known relations from the literature.