HY8:Irregular Channel

An irregular channel cross section option defines a channel using the channel slope and the station, elevation, and Manning's n at each input coordinate point. The minimum and maximum number of coordinates allowed to define a channel shape are 3 and 15 (see Figure below). All coordinates and n values may be copied from Microsoft Excel and pasted into the table. After all data have been entered, the user can plot and view the channel cross section looking downstream.

File:HY8image51.gif

Figure 1. Irregular Channel Tailwater Editor.

Manning's n is defined as shown in the figure below. An n value is assigned for each segment of the cross section beginning at the left (looking downstream) coordinate (below). If the n value is the same throughout the cross section, the user may copy the n value be dragging the value from the first cell.

File:HY8image54.gif