Duct fitting pressure drop coefficients for
rectangular and round wyes
From ASHRAE (1989), with permission
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Values of Cc,1b or Cc,2b for a converging Wye
|
V1b / Vc or V2b / Vc |
|||||||||||
0 |
0.1 |
0.2 |
0.3 |
0.4 |
0.5 |
0.6 |
0.7 |
0.8 |
0.9 |
1.0 |
||
q, deg | 15 |
-2.6 |
-1.9 |
-1.3 |
-0.77 |
-0.30 |
0.10 |
0.41 |
0.67 |
0.85 |
0.97 |
1.0 |
30 |
-2.1 |
-1.5 |
-1.0 |
-0.53 |
-0.10 |
0.28 |
0.69 |
0.91 |
1.1 |
1.4 |
1.6 |
|
45 |
-1.3 |
-0.93 |
-0.55 |
-0.16 |
0.20 |
0.56 |
0.92 |
1.3 |
1.6 |
2.0 |
2.3 |
V1b / Vc or V2b / Vc |
||||||||||||||
0.1 |
0.2 |
0.3 |
0.4 |
0.5 |
0.6 |
0.8 |
1.0 |
1.2 |
1.4 |
1.6 |
1.8 |
2.0 |
||
q, deg | 15 |
0.81 |
0.65 |
0.51 |
0.38 |
0.28 |
0.20 |
0.11 |
0.06 |
0.14 |
0.30 |
0.51 |
0.76 |
1.0 |
30 |
0.84 |
0.69 |
0.56 |
0.44 |
0.34 |
0.26 |
0.19 |
0.15 |
0.15 |
0.30 |
0.51 |
0.76 |
1.0 |
|
45 |
0.87 |
0.74 |
0.63 |
0.54 |
0.45 |
0.38 |
0.29 |
0.24 |
0.23 |
0.30 |
0.51 |
0.76 |
1.0 |
|
60 |
0.90 |
0.82 |
0.79 |
0.66 |
0.59 |
0.53 |
0.43 |
0.36 |
0.33 |
0.39 |
0.51 |
0.76 |
1.0 |
|
90 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |