the S-wise span between 0.5 < S/SL < 1 on the endwall of present
sharp bend as indicated by Fig. 4(g), the obtuse-to-acute Nu decrease
in the span of 0 < S/SL < 0.5 is reversed to the obtuse-toacute
Nu increase after entering the turning region. The obtuseto-
acute Nu increase emerging over the bend endwall along rib 6
shown by Fig. 4(h) suggests that the sweeping flow over the turning
endwall by the swirls through present sharp bend is directed
from the outer top wall toward the inner curved bend. As the
near-wall flows driven by such Dean-type vortical flows through
the bend act in the same direction with those tripped by the angled
ribs deployed over the outlet-leg endwall, the obtuse-to-acute Nu
decreases consistently emerge all over the outlet-leg endwall,
Fig. 4(i)–(l) and (m)–(p). As the S-wise Nu variations over present
sharp bend endwall follow the consistent decreasing trend from
the outer wall toward the inner edge of the central divider, the
swirls induced through the sharp bend for each of present test
channels are dominantly generated by the centrifugal forces. Over
rib 5–6 on the endwall of the outlet leg, the typical S-wise Nu profiles
subject to the consistent obtuse-to-acute decreases are recovered,
Fig. 4(m)–(p).