Results (T_w step drops) agreed reasonably well with that from experiments (T_w continuously drops).

A positive gradient in porosity promoted solidification evolution relative to uniform cases.

For Cu foams with hollow ligaments, a negative gradient in pore density enhanced solidification.

For Al foams with solid ligaments, a gradient in pore density had little effect on solidification.

Placing foam with higher conductivity next to cooling boundary led to further enhanced phase change.