Mario

Presentation of results - Inspire / Hyperview

Recommended Posts

Mario    8

Hello,

I have a question regarding the presentation of results.

Find attached two pictures of the same result presented in Inspire and Hyperview (from scratch directory. fem & h3d).

You can see the result of a screw pretension. The stress distribution look extremely different and i'm a little bit surprising.

Is there any reason for that?

 

Best Regards,

Mario

 

Pretension_Inspire.png

Pretension_Hyperview.png

Pretension.stmod

Share this post


Link to post
Share on other sites

Hi Mario,

please share your element size and type (first or second order), so I can try to reproduce your issue.

Thanks!

BR

Felix

 

Share this post


Link to post
Share on other sites
Mario    8

Hi again,

The "Autocalculate Meshsize" of both parts is switched off and min. is 1mm, max is 5mm.

There is nothing more to do, only run a calculation. If it is not comprehensibly, then i can send also results (but the file is much bigger, since you need also the h3d for Hyperview).

Version i'm using is Inspire 2017.3.1 build 8625.

Best Regards,

Mario

 

Share this post


Link to post
Share on other sites

Hi Mario,

HV vs. Inspire.png

By default, Inspire is using Grid Point Stresses, so we have to choose them in HV to compare. I also slightly adjusted the min/max in the Inspire legend.

Hope this helps!

 

Best Regards,

Felix

Share this post


Link to post
Share on other sites
Mario    8

Hi Felix,

 

Thank you for the explanation, now I can understand it.

Unfortunately, this does not improve the plausibility of the result.

 

Best Regards,

Mario

 

Share this post


Link to post
Share on other sites

Hi Mario,

You have supported the lower plate. So the stress results of pretension must be asymetric.

Or do you see something else?

BR

Felix

Share this post


Link to post
Share on other sites
Mario    8

Hi Felix,

The asymmetry is not the problem, but the stress distribution does not look plausible.

Corresponding to the pressure cone (area) of a screw connection, the highest load should occur at the top.

 

Best Regards,

Mario

 

Share this post


Link to post
Share on other sites

Mario,

You might would like to decrease element size to get a more detailed look at the stress distribution. For my point of view, there is all right.

 

We can clearly see the maximum peak of sheer stresses below the surface - so the van mises stresses.

This effect is discribed in the Hertzian compression theory, which can also explain defects like pitting.

 

BR

Felix

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now