Melting and solidification
PIV studies, using a transparent alloy (NH4Cl), of the interaction between the solidification and the flow
- Different flow regimes were observed during solidification.
- In area with a high amount of equiaxed crystals the turbulence of the flow is damped. The flow is dragged by equiaxed crystals.
- The relative velocity between crystals and flow was calculated. A power tendency was found between the relative velocity of isolated crystals and the crystal diameter.
- For high flow velocity and large solidification front velocity, equiaxed crystals were observed.
- Clear correlation between flow kinetic energy and occurrence of equiaxed crystals were observed. The flow KE always presents a peak during the equiaxed crystals‘ rain.
- Coupling mechanism between flow intensity and equiaxed crystals occurrence was proposed, which can explain CET.
Dual PIV-Setup to study columnar & equiaxed solidification
