Cross-sections
Some Stage-Discharge transformation functions need cross-sectional profiles at the water level measuring locations upstream and downstream of a structure to compute the velocity head and the submergence ratio. Through the function 'Cross-Sectional Profiles' of the Entry and Edit function map these profiles can be entered.
To add or edit profile data, select a series from the Station codes list box. If some data for this station already exists it will be shown in your form. With the spin button you can increase or decrease the <Number of sections> in your profile. Per section you can enter the distance and level from a reference point. A station can have many cross-section data, they are defined by a date and a name (i.e. Upstream, Central and Down-stream).
Press <Update Graph> to show a graph in the small graph window of the input form. This graph is not directly linked to the spreadsheet. Each time you change values in the spreadsheet and want to see your new values in the graph, it is necessary to press the <Update Graph> button. To clear the graph, press the <Clear Graph> button. If you want to see a large graph from the cross section data you can send the data to the main graph program by pressing the <Large Graph> button. From this main graph program you can print the cross section or copy the cross section graph to the clipboard.
Press <Add New> to add a new cross section, <Save> to save the entered information in the database, <Delete> to delete a cross-sectional profile from the database, <Close> to leave the window without saving.
It is also possible to add a cross section by importing it from a file. First select the series you want to import a cross section for, and then press on the <Import> button. Select a filename from the File open Dialogue and save the new data to the database by pressing the <Save> button.
For a cross-section some properties can be computed by pressing the <Compute Properties> button. The following form will appear:
A Cross-section can be split in different horizontal sections by changing the "# Section" and entering the left and right boundary of a section. Calculation of the properties is done for each section at different vertical levels. The results of the calculation can be viewed by pressing <Report> in the main HYMOS function window.
Format of the Cross-section file
The cross section data must be entered and stored in ASCII files with "*.crs" as extension. The format of the files is as follows:
Cross-sectional data station Nong Khai
1988,11,20
Dist. from initial point, level, correction
0,0,0
13.2,-5.8,0
33.2,-10,0
53.2,-11.8,0
73.2,-11.5,0
93.2,-6.2,0
113.2,- 4.3,0
133.2,0,0
- The first line contains information about the location where the cross-section is measured.
- The second line contains the year, month and day of the measurement.
- The third line contains information about the rest of the file.
- Lines 4 and further contain the values of the distance from the initial point, the level of the river bottom and the corrected level (corrected level is not used at the moment).
