Laserfiche WebLink
<br />ChapteT 3 WaTkin", With HEC-RAS . An Overview <br /> <br />disk. This is accomplished by selecting the Save Geometric Data As option <br />from the File menu on the Geometric Data editor. This option allows the user <br />to enter a title for the geometric data. A filename is automatically established <br />for the geometric data, and then saved to the disk. Once a title is established, <br />geometric data can be saved periodically by selecting Save Geometric Data <br />from the File menu of the Geometric Data editor. <br /> <br />Entering Flow and/or Sediment Data <br /> <br />Once the geometric data are entered, the modeler can then enter any flow <br />andlor sediment data that are required. The type of data that are entered will <br />depend on the type of analysis that is going to be performed. If the modeler is <br />performing a steady flow analysis, then Steady Flow Data must be entered. If <br />an unsteady flow analysis is going to be performed, then Unsteady Flow Data <br />must be entered. Likewise, if the modeler is going to perform sediment <br />transport calculations, then Sediment Data must be entered. Data entry forms <br />for these various types of data are available under the Edit menu bar option on <br />the HEC-RAS main window. <br /> <br />An example of the flow data entry form is shown in Figure 3.6, which is the <br />Steady Flow Data form. As shown in Figure 3.6, Steady Flow Data consist <br />of: the number of profiles to be computed; the flow data; and the river system <br />boundary conditions. At least one flow must be entered for every reach within <br />the system. Additionally, flow can be changed at any location within the river <br />system. Flow values must be entered for all profiles. <br /> <br />Boundary conditions are required in order to perform the calculations. If a <br />subcritical flow analysis is going to be performed, then only the downstream <br />boundary conditions are required. If a supercritical flow analysis is going to <br />be performed, then only the upstream boundary conditions are required. If the <br />modeler is going to perform a mixed flow regime calculation, then both <br />upstream and downstream boundary conditions are required. The Boundary <br />Conditions data entry form can be brought up by pressing the Enter <br />Boundary Conditions button from the Steady Flow Data entry form. <br /> <br />Once all of the steady flow data and boundary conditions are entered, the <br />modeler should save the data to the hard disk. This can be accomplished by <br />selecting Save Flow Data As from the File option on the Steady Flow Data <br />menu bar. Flow data is saved in a separate file. The user is only required to <br />enter a title for the data, the filename is automatically assigned. <br /> <br />3-7 <br />