Discontinuous Opening

The discontinuous opening is the downstream element of the boundary element pair defining a change in channel slope. The following constants have to be specified on the line beneath the *FLUID SECTION,TYPE=CHANNEL DISCONTINUOUS OPENING card:

• the width
• (Figure 122; if the slope is calculated from the coordinates of the end nodes belonging to the element)
• the length (Figure 122; if the length is calculated from the coordinates of the end nodes belonging to the element)
• the trapezoid angle
• the grain diameter for the White-Colebrook law or the Manning constant for the Manning law (in the latter case the user has to specify the parameter MANNING on the *FLUID SECTION card)
• the number of the upstream discontinuous slope element.

The length is typically small compared to the length of the adjacent channel branches.

Example files: channel6.