11
114.
9.1
0.000098
0.0271
7.51
2.07
0.12
0.06
LO
12
125.
8.7
0.000098
0.0269
7.27
2.05
0.12
0.05
LO
13
135.
8.3
0.000098
0.0266
7.04
2.03
0.12
0.05
LO
14
146.
7.9
0.000098
0.0264
6.82
2.01
0.13
0.05
LO
15
156.
7.5
0.000099
0.0262
6.61
1.99
0.13
0.05
LO
16
166.
7.2
0.000100
0.0260
6.40
1.97
0.13
0.05
LO
17
177.
6.9
0.000101
0.0258
6.21
1.96
0.13
0.04
LO
18
187.
6.7
0.000102
0.0256
6.02
1.94
0.13
0.04
LO
19
198.
6.4
0.000103
0.0255
5.84
1.93
0.13
0.04
LO
20
208.
6.2
0.000105
0.0253
5.68
1.91
0.14
0.04
LO
RESULTS AT MINIMUM STREAM POWER
21
118.
9.0 0.000098 0.0270
7.43
2.07
0.12
0.05
LO
* REGIMES:
LO=LOWER, TL=TRANSITIONAL-LOWER, TU=TRANSITIONAL-UPPER, UP=UPPER.
...END OF JOB...
Table 4-1 contains the family of widths, depths, and slopes which satisfies the
sediment transport and resistance equations for the given conditions. It is
important to consider river morphology when interpreting these calculated
values. That is, each line in the table satisfies the governing equations, but
natural rivers tend toward a regime width. Consequently, the calculations start
with the regime width as determined by the following equation:
B = 2.0 Q0.5
For the water discharge in this example, the equation gives a regime width of
120 feet. This regime width is then divided by 10 to provide a starting value for
the table, 12 ft in this case. The rest of the table is produced by adding the 12 ft
increment to each successive width and repeating the depth, slope, n-value
calculations. Note the last column in the table, "Flow Regime." Four conditions
are possible:
LO = Lower regime
(i.e. ripples and dunes)
TL = Transition zone, Lower regime selected
(bed forms tend towards ripples and dunes.)
TU = Transition zone, Upper regime selected
(Bed forms tend toward plain bed.)
UP = Upper regime selected
(Plain bed and antidunes)
Channel dimensions corresponding to minimum stream power, Q*S , (which
also corresponds to minimum slope), are presented at the bottom of the table. In
this example the energy slope reaches a minimum value at about the regime
width. However, that is not always the case. Much depends on the bank
roughness.
These calculations will provide the information to plot the stable channel
dimension curve,
118
Chapter 6
Input Requirements and Program Output for SAM.hyd
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