The experimental results in Fig. 5

The experimental results in Fig. 5 suggest that the
pin fins provided the highest heat transfer rate and
the least time to mold parts. This is due to the fact
that, based on the total volume; the pin fin has the
largest total surface area (Table 2), and heat transfer
rate is increased by increasing the surface area
across which the convection occurs. Surprisingly,
despite the total surface of the triangular fin being
smaller than that of the pin fin, the triangular fin
exhibited about the same heating/cooling efficiency
as that of the pin fin. This may be because the entire
potential heat transfer surface has been fully utilized
in the fins. For pin fins, part of the surfaces,
especially the surfaces that face the opposite
direction of the airflow, may not be exposed very
well to the air. On the contrary, based on the
rotating direction of the mold, the surfaces of the
triangular fins were fully utilized (see Figs. 2 and 3).
Triangular fins thus exhibit similar efficiency as that
of pin fins