Enhancements and Modifications to the Full Equations Utilities (FEQUTL)
Model, March 1995 to August 1999.
Note: This document is separate from the U.S. Geological Survey report by Franz and Melching (1997). This description of enhancements and modifications to the Full Equations Utilities Model has not been approved by the Director of the U.S. Geological Survey.
Input description update for section 5.6, EMBANKQ Command, Franz and Melching (1997b), p. 106
Section 5.6 EMBANKQ Command
|Variable:||TABLE, TYPE, HLCRIT, HLMAX, HSCALE, VSCALE, CSHIFT|
|Format:||7X, I5, A5, A5, 8X, F10.0, 8X, F10.0, 8X, F9.0|
|Gives table number for the table to be computed by FEQUTL and several optional parameters. TYPE can be either 6 or 13 with 13 taken by default if TYPE is omitted. HLCRIT gives the critical ratio between approach head and embankment width that distinguishes between low-head and high-head flow. Ratios less than HLCRIT are taken to be low-head flow and ratios at or greater than HLCRIT are taken to be high-head flow. HLMAX gives the maximum ratio of approach head to embankment width that can be used without generating a warning message from EMBANKQ. This warning message alerts the user to the possibility that the weir coefficients may no longer be valid at head ratios greater than HLMAX. If omitted HLCRIT defaults to 0.15 and HLMAX to 0.32, the values taken from Hulsing(1967) and Kindsvater(1964). HLMAX represents the approximate upper limit of the head-to-width ratio in the experiments defining the weir coefficients.|
|HSCALE gives the horizontal scale factor for the offsets along the crest. VSCALE gives the vertical scale factor for the elevation measurements for the crest and for the approach elevations. These two values are given the value 1.0 if they are omitted. They prove useful for stream systems in which two different unit systems are in use. The field measurements for each region can appear in the input so that they can be checked easily. Then the system of units that differs from the one to be used in FEQ is converted to be consist.|
|CSHIFT gives the shift in the crest elevation. This is useful for railroad embankments when the elevation of the ties is often given. The shift to the top of rail can then be added. It is possible to use EMBANKQ to estimate flow through the ballast on the roadbed. In this case the value of CSHIFT would be negative. The weir coefficient tables would have to be modified to force a weir formula to approximate the variation of seepage through the ballast.|