What we're talking about here is flow-induced vibration. Outside of some type of Computational Fluid Dynamics software it would be impossible to predict. This is done in Caesar II not predictively, but rather after a system in operation is experiencing a vibration problem. In such a case you need measurements of displacements throughout your piping system (or at least in several locations around the problem area). Then using Caesar II's harmonic analysis routines you use trial and error (changing the harmonic force location and magnitude) until you match Caesar II's dynamic output displacements to that measured. At that point you know you have a good Caesar II model and can make corrective changes from there.
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Loren Brown
Director of Technical Support
CADWorx & Analysis Solutions
Intergraph Process, Power, & Marine
12777 Jones Road, Ste. 480, Houston, TX 77070 USA