Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Error in Harmonic analysis - Mode superposition method- ANSYS workbench

Status
Not open for further replies.

Premmit

Aerospace
Aug 16, 2015
1
Hi,

I am performing mode superposition method harmonic analysis in ANSYS workbench v14. My component is attached to a large mass (1E6 times the component mass) and the large mass is released in z-direction. In modal analysis I have provided modal damping and Freq Vs. Force (Large mass* acceleration in g *9.81) excitation curve using APDL commands (to support this I have added a remote force at the large mass remote point and provided a dummy force in z-direction). The modal analysis soln. is linked to harmonic analysis to perform mode superpostion harmonic analysis. The harmonic analysis result(.rst) is opened in Mechanical APDL. When I extract the acceleration at the input excitation point (large mass) the excitation curve is followed, thus verifying the run.

Later, I added few point masses to the analysis which is connected to some surfaces in the model. These point masses are defined as deformable. When I extracted the results for the second model, I find the results are bogus. Even the input excitation curve at the largemass is not observed, I observe the input is very large where the component goes to 1e9 meter displacement. This error is not observed when the point masses are suppressed and the results makes sense. Please let me know if anyone encountered similar error.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor