Duct fitting pressure drop coefficients for
blast gate

From ASHRAE (1989), with permission

A5-6l.gif (11014 bytes)

h / D

Ah / A0

C0

0.2

0.25

35

0.3

0.38

10

0.4

0.50

4.6

0.5

0.61

2.1

0.6

0.71

0.98

0.7

0.81

0.44

0.8

0.90

0.17

0.9

0.96

0.06