Applies To
	Product(s):	AutoPIPE
	Version(s):	V8i
	Area:	Modeling
	Original Author:	Darius Rimasauskas, Bentley Technical Support Group

Problem: 

The following warning appears when inserting Nozzle, how to resolve?

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Warning
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W79-85:   0 Stiffness in direction of imposed harmonic load. at XXX
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OK
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What should I do to avoid this warning message?

Solution:

The intent of this message is to let the user know that no support was found at the specified node point. When setting the Harmonic Input to:

• Impose Acc. (Gravity)

• Impose Acc. 

• Impose Displacement

• Impose Velocity

A support will need to be defined at each of the indicated node Points mentioned on the Harmonic Load dialog.

Example:   

In this example, a support must be added to both node points; A04 and A09.

Note, If no support was added to node point A04, then the warning message above would appear when running an analysis.. 

Workaround:

a. Add a support to node point A04

or

b. Change the harmonic load case Input from "Impose Displacement" to "Impose Force" 

Remember that Impose support displacement, acceleration, and Velocity are only applied to the base of the support spring:

     

The stiffness factor of the support determines the amount of movement that is transferred from the base of the support to the other end of the support spring. A support with rigid stiffness should transfer 100% of base movement to the other end of the support spring, and ultimately to the pipe being supported minus   direction of support restraint(s). 

CAE development team may update this message to say:

W79-85:  No support in direction of imposed harmonic load at xxx