Duct fitting pressure drop coefficients for
round, diverging conical branch tees
From ASHRAE (1989), with permission
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Branch Cc,b
vb / vc |
0 |
0.2 |
0.4 |
0.6 |
0.8 |
1.0 |
1.2 |
1.4 |
1.6 |
1.8 |
2.0 |
Cc,b | 1.0 |
0.85 |
0.74 |
0.62 |
0.52 |
0.42 |
0.36 |
0.32 |
0.32 |
0.37 |
0.52 |
Main Cc,s
vs / vc |
0 |
0.1 |
0.2 |
0.3 |
0.4 |
0.5 |
0.6 |
0.8 |
1.0 |
Cc,s | 0.40 |
0.32 |
0.26 |
0.20 |
0.14 |
0.10 |
0.06 |
0.02 |
0 |