Are minor losses from pipe bends automatically considered?

Product(s): WaterGEMS, WaterCAD, HAMMER, SewerGEMS, CivilStorm, StormCAD, SewerCAD
Version(s): 08.11.XX.XX+, 10.XX.XX.XX
Area:  Layout and Data Input

Problem

Will the minor losses associated with pipe bends be automatically accounted for?

Solution

Water products (WaterCAD, WaterGEMS, HAMMER)

No, you must enter the appropriate minor loss coefficient in the properties of the pipe. A library of typical values for various bend angles are included, which you can choose from. 

We have a minor loss engineering library that can be accessed through the "Minor Losses" property in the appropriate element, which can be accessed by clicking on the ellipsis button.

Step 1:

Step 2:

Storm & Sewer products (SewerGEMS, SewerCAD, StormCAD, CivilStorm)

Headloss/minor loss from bends are not automatically accounted for. These are usually small enough that the user will typically ignore them in a hydraulic model.

If there is a structure located at the bend (manhole, catch basin or transition), you can account for loss through the structure using one of the available Structure Loss Methods, found in the properties of the node. For example with the AASHTO method, it calculates the bend angle of the adjacent pipes and uses that.

There is also an option to enter an entrance and exit loss coefficient on the conduit.

Or, you could potentially account for additional loss by adjusting the friction factor of the pipe. If in doubt, consider a sensitivity analysis by increasing and decreasing the friction losses to see what effect it has on the results. If it does not significantly impact them, you won’t need to worry about it. If they do, you could make a conservative assumption. The decision is up to the modeler and engineer.

Anonymous
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