Page 110 - Fair, Geyer, and Okun's Water and wastewater engineering : water supply and wastewater removal

JWCL344_ch03_061-117.qxd 8/17/10 7:48 PM Page 73

3.10 Nonsteady Radial Flow 73
Table 3.2 Values of the Well Function W(u) for Various Values of u

u
N N 10 15 N 10 14 N 10 13 N 10 12 N 10 11 N 10 10 N 10 9 N 10 8
1.0 33.96 31.66 29.36 27.05 24.75 22.45 20.15 17.84
1.5 33.56 31.25 28.95 26.65 24.35 22.04 19.74 17.44
2.0 33.27 30.97 28.66 26.36 24.06 21.67 19.45 17.15
2.5 33.05 30.74 28.44 26.14 23.83 21.53 19.23 16.93
3.0 32.86 30.56 28.26 25.96 23.65 21.35 19.05 16.75
3.5 32.71 30.41 28.10 25.80 23.50 21.20 18.89 16.59
4.0 32.56 30.27 27.97 25.67 23.36 21.06 18.76 16.46
4.5 32.47 30.15 27.85 25.55 23.25 20.94 18.64 16.34
5.0 32.35 30.05 27.75 25.44 23.14 20.84 18.54 16.23
5.5 32.26 29.95 27.65 25.35 23.05 20.74 18.44 16.14
6.0 32.17 29.87 27.56 25.26 22.96 20.66 18.35 16.05
6.5 32.09 29.79 27.48 25.18 22.88 20.58 18.27 15.97
7.0 32.02 29.71 27.41 25.11 22.81 20.50 18.20 15.90
7.5 31.95 29.64 27.34 25.04 22.74 20.43 18.13 15.83
8.0 31.88 29.58 27.28 24.97 22.67 20.37 18.07 15.76
8.5 31.82 29.52 27.22 24.91 22.61 20.31 18.01 15.70
9.0 31.76 29.46 27.16 24.86 22.55 20.25 17.95 15.65
9.5 31.71 29.41 27.11 24.80 22.50 20.20 17.89 15.59
u
N N 10 7 N 10 6 N 10 5 N 10 4 N 10 3 N 10 2 N 10 1 N
1.0 15.54 13.24 10.94 8.633 6.332 4.038 1.823 2.194 * 10 -1
1.5 15.14 12.83 10.53 8.228 5.927 3.637 1.465 1.000 * 10 -1
2.0 14.85 12.55 10.24 7.940 5.639 3.355 1.223 4.890 * 10 -2
2.5 14.62 12.32 10.02 7.717 5.417 3.137 1.044 2.491 * 10 -2
3.0 14.44 12.14 9.837 7.535 5.235 2.959 0.9057 1.305 * 10 -2
3.5 14.29 11.99 9.683 7.381 5.081 2.810 0.7942 6.970 * 10 -3
4.0 14.15 11.85 9.550 7.247 4.948 2.681 0.7024 3.779 * 10 -3
4.5 14.04 11.73 9.432 7.130 4.831 2.568 0.6253 2.073 * 10 -3
5.0 13.93 11.63 9.326 7.024 4.726 2.468 0.5598 1.148 * 10 -3
5.5 13.84 11.53 9.231 6.929 4.631 2.378 0.5034 6.409 * 10 -4
6.0 13.75 11.45 9.144 6.842 4.545 2.295 0.4544 3.601 * 10 -4
6.5 13.67 11.37 9.064 6.762 4.465 2.220 0.4115 2.034 * 10 -4
7.0 13.60 11.29 8.990 6.688 4.392 2.151 0.3738 1.155 * 10 -4
7.5 13.53 11.22 8.921 6.619 4.323 2.087 0.3403 6.583 * 10 -6
8.0 13.46 11.16 8.856 6.555 4.259 2.027 0.3106 3.767 * 10 -5
8.5 13.40 11.10 8.796 6.494 4.199 1.971 0.2840 2.162 * 10 -5
9.0 13.34 11.04 8.739 6.437 4.142 1.919 0.2602 1.245 * 10 -5
9.5 13.29 10.99 8.685 6.383 4.089 1.870 0.2387 7.185 * 10 -6
Source: After U.S. Geological Survey.

where
2
u = 1.87(S>T)(r >t) (U.S. Customary Units) (3.16)
and T is transmissivity in gpd/ft.
The equation can be solved for any one of the quantities involved if other parameters
are given. The solution for drawdown, discharge, distance from the well, or time is
straightforward. The solution for transmissivity T is difficult, because it occurs both inside