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FSI: inconsistent number of eigenvalue

Hello everyone,

I want to do flexible riser simulation. riser pinned at two end (constrain at xyz translation, free xyx rotation) + upward force (top tension) define as load. The loadsteps in optistruct are:

1. Linear static:

spc: defined
load: defined

2. modal Analysis:
spc: defined

method (struct): defined

statsub (preload): linear static

I get an error during importing op2 file into acuconsole-eigenmode manager.

<?xml version="1.0" encoding="UTF-8"?>

The error only occur when there are two subcase (linear static + modal analysis). If i only do modal analysis without linear static, i can import the op2 file without any error.

attached is the optistruct and acusolve file.

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acupro

It may be that the OP2 file for Eigenmode Manager can only contain output from the modal analysis subcase - so maybe make sure there is no output requested for the linear static subcase.

Nazrin

Dear /profile/5282-acupro/?do=hovercard' data-mentionid='5282' href='<___base_url___>/profile/5282-acupro/' rel=''>@acupro,

so maybe make sure there is no output requested for the linear static subcase.

How can I exclude linear analysis in 'output: op2 card'?

acupro

Sorry - I'm not an OptiStruct user. You may need to ask that question in the OptiStruct forum. Describe the two load cases, and indicate you don't want to write output from the first load case (Linear Static) to the OP2 file. You only want output from the Frequency/Modal load case written to the OP2 file. Probably include the .hm file again, too.