Qfull in #SWMM5 and #INFOSWMM for various levels of y/yFull in a Circular Pipe
Subject: Qfull in SWMM 5 for various levels of y/yFull in a Circular Pipe
Here is a table that shows the value of Q/Qfull for various levels of y/yFull or d/D in SWMM5. The full flow if you loop off the top of a circular pipe at the 0.83 level would be about 1.01 times Qfull for the whole pipe. Figure 1 shows how the flows are calculated at various values, Table 1 and Figure 2 show the values of a/aFull, r/rFull and q/qFull for various values of y/yFull.
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| Figure 1. How Qfull and Qmax are calculated in SWMM 5 based on the roughness, slope and a lookup table for area and hydraulic radius for a circular pipe. |
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| Figure 2: A/Afull vs y/Yfull for a circular pipe |
y/yFull | a/aFull | r/rFull | Q/qFull |
0.00000 | 0.00000 | 0.01000 | 0.00000 |
0.02000 | 0.00471 | 0.05280 | 0.00066 |
0.04000 | 0.01340 | 0.10480 | 0.00298 |
0.06000 | 0.02445 | 0.15560 | 0.00707 |
0.08000 | 0.03740 | 0.20520 | 0.01301 |
0.10000 | 0.05208 | 0.25400 | 0.02089 |
0.12000 | 0.06800 | 0.30160 | 0.03058 |
0.14000 | 0.08505 | 0.34840 | 0.04211 |
0.16000 | 0.10330 | 0.39440 | 0.05556 |
0.18000 | 0.12236 | 0.43880 | 0.07066 |
0.20000 | 0.14230 | 0.48240 | 0.08753 |
0.22000 | 0.16310 | 0.52480 | 0.10612 |
0.24000 | 0.18450 | 0.56640 | 0.12630 |
0.26000 | 0.20665 | 0.60640 | 0.14805 |
0.28000 | 0.22920 | 0.64560 | 0.17121 |
0.30000 | 0.25236 | 0.68360 | 0.19583 |
0.32000 | 0.27590 | 0.72040 | 0.22172 |
0.34000 | 0.29985 | 0.75640 | 0.24893 |
0.36000 | 0.32420 | 0.79120 | 0.27733 |
0.38000 | 0.34874 | 0.82440 | 0.30662 |
0.40000 | 0.37360 | 0.85680 | 0.33702 |
0.42000 | 0.39878 | 0.88800 | 0.36842 |
0.44000 | 0.42370 | 0.91760 |


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