Prismatic channel

This refers to an open channel that has the same cross-section and bed slope throughout. This may have a rectangular, trapezoidal, semi-circular or other cross-sectional shape. Note that rectangular and triangular shapes are special cases of the trapezoidal shape.

        

In DRAINS the term is used to define man-made trapezoidal channels. Strictly speaking, however, a natural channel with an irregular shape is prismatic, as long as the cross-section and bed slope are constant along its length.

Details of prismatic channels are specified in a property sheet.

Following a run, flowrates through a channel and water levels at its ends can be viewed in the Main Window display. Options for displaying more detailed results are given in the Pop-Up (right mouse button) menu.  View Cross Sections provides a display showing the channel cross section and the peak water levels at each cross section entered.

​

• Related Articles

• Prismatic open channel drawing tool

  This tool, , enables you to draw a prismatic channel in the Main Window. When you select it, the arrow cursor changes to a pencil that draws a channel by clicking on the upstream and downstream end points. (You can enter several channel reaches ...

• Prismatic Open Channel property sheet

  This window shows a diagram of a trapezoidal open channel, with text boxes in which the bottom width, side slopes and height can be entered or displayed. Asymmetric channels with different side slopes on each side can be accommodated. For vertical ...

• Multi-channel property sheet

  This box allows you to specify data for multiple channels or pipes connecting between the same nodes or pits. This is a situation that may arise when systems are amplified. The dialog box simply requests or displays a multi-channel name (a default ...

• Irregular open channel property sheet

  In this window you can enter and review data for open channels that: are prismatic but have a shape other than trapezoidal, triangular or rectangular, or do not have a regular cross-sectional shape, such as sections that occur with a natural stream ...

• Multi-channel

  This is a type of link used in DRAINS to model complex multiple pipes located between the same nodes or pits, as in the example below: You can specify various combinations of open channels and pipes using the Multi Channel property sheet. Any number ...