| Applies To | |||
| Product(s): | AutoPIPE | ||
| Version(s): | All | ||
| Environment: | N/A | ||
| Area: | Analysis | ||
| Original Author: | Bentley Technical Support Group | ||
| Date Logged & Current Version | June 2015 09.06.02.06 | ||
Problem:
No Dynamic Harmonic load case affect on piping model with force files generated by PULS in AutoPIPE, why?
Hello,I have modeled a pipe installation and exported the files to PULS to run pressure pulsation analysis. I have saved the force files that were created but when I go into AutoPipe I cant get the model to react to the file. I can see the file and have selected it in the dynamic analysis tab but when I run the analysis there doesn't seem to be any effect on the pipework.
Solution:
Be sure that the Modal analysis and Harmonic load case are configured correctly on the AutoPIPE Dynamic load case dialog (Modal & Harmonic tabs). If these are configured correctly, initiate the Analyze ALL command to analyze the model. This dialog should have the following minimum settings:
After the analysis has finished, check the Combinations dialog to be sure that the harmonic load case has been analyzed and is apart of the Code and Non-code combinations:
To review the contributions of the Harmonic load case on the piping arrangement, animate the model per Harmonic displacement results, Results> Displacements> Load Combination = Harmonic> enable "Animate Load Case" option:
The model should now be overly exaggerated in the amount of animation movement( note: change the Results Model options> Displacement Scale setting to adjust the amount of exaggeration).
As can be seen by the image above the Harmonic load case does in fact affect the model. However, notice the amount of displaced movement in all directions, ex. 0.001 in.
Review the same results in the results grids:
Essentially most of the values appear to be 0.00, but upon closer examination they are actually very small values (ex. 7.3790514e-012). Thus giving the appearance of no contribution from the harmonic load case.
In this case the Harmonic load is correctly configured, analyzed, and results displayed; just that the amount of affect on this model from this particular Harmonic load is very small