Surfaces

# of channels/holes/ mushroom fins

Area augmentation ratio (A_r)

β

Plain

---

1

--

Mushroomed

45 mushroom fins

1.12

1.67

Holed 1

77 holes

1.15

2

Holed 2

187 holes

1.37

1

Holed 3

405 holes

1.81

0.5

Grooved 1

9 channels

1.328

3.75

Grooved 2

17 channels

1.62

2

Grooved 3

27 channels

1.98

1