(a)
(b)
(c)
(d)
(e)
(f)
Figure 12: Turbulent kinetic energy contours (m2/s2) of the wing-shaped tubes for different fin heights () at Re = 9700: (a) = 2 mm, (b) = 4 mm, (c) = 6 mm, (d) = 8 mm, (e) = 10 mm, and (f) = 12 mm.