Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

simple linear static

mpvnaresh

I am running a simple linear static analysis

I think the output stresses are not correct.I am attaching my fem and output file.

Please some one tell me what is the mistake ..i am unable to find where i went wrong.

Unable to find an attachment - read this blog

Find more posts tagged with

English

OptiStruct

Accepted answers

All comments

Rahul Rajan_21763

FEA setup and output looks logical to me. In HyperView I checked average (simple option)Von Mises stresses.

Are you expecting the same stresses for 2d longitudinal and vertical?

I also see you named load collector as 2G. In FEA gravitation load is not considered by default. You have to define explicitly gravitational load using GRAV card in load collector.

mpvnaresh

I ACTUALLY HAVE NO TEST DATA ...I HAVE NO RESULTS TO COMPARTE ...I AM NOT CONSIDERING THE WEIGHT OF THE PLATE ....I AM APPLYING A DEAD MASS WHICH IS CAUSED BY SOME OTHER COMPONENT BOLTED TO THE PLATE ...FOR 2g AND 3g ...ETC

THE STRESSES ARE LOOKING VERY LOW. SO THAT IS WHY I DOUBTED.

mpvnaresh

SHOULD I COMPARE WITH 2d ALSO ?

mpvnaresh

I compared with 2D also .....

The displacement magnitudes for all the subcases are same for 2D and 3D elements , But Component displacements are different.

coming to stresses average and un averaged stresses are same for 3D elements for all subcase ,same thing observed for 2D also.

But when comparing stresses of 2D elements and 3D elements ,There is a stresses difference of magnitude depending on range..

for very small ranges of stresses there is no difference.

mpvnaresh

any suggestions ?

Rahul Rajan_21763

Stress variation depends upon several factors:(load magnitude/mesh/Post processing in Hyperview elemental or nodal with averaging and unaverage option)

By default OptiStruct gives elemental centroid based results.If you want to compare nodal average results then set the control card : Global output request: Stress:Location : corner .This will enable corner option in HypervIew while postprocessing stress results.

mpvnaresh

Thanks Sir