Simulation Mechanical and Multiphysics

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MattKurtze5538
Posts: 15
Registered: ‎10-27-2010

Load Envelopes

176 Views, 4 Replies
12-29-2011 12:13 AM

Hello All

 

I mainly perform FEA on silos to the AS bulk loading code.  This requires MANY load case combinations of bulk/friction/EQ/wind ect.

 

Currently i am setting up each load case as a separate DS then creating the combinations in separate file.

 

What i want to do then is combine all load case combinations from that fine into an envelope case. ie superimposing the combinations (without adding them) and displaying the max results from all combinations in one results window.  This allows me to easily see is there are any issues without having to individually check 20 combinations.

 

I was able to easily do this in my previous package, Strand7.  Is there a way to do it with autodesk.

 

Regards 

 

Matt

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INACTIVE_AstroJohn
Posts: 492
Registered: ‎03-25-2010

Re: Load Envelopes

01-03-2012 06:09 AM in reply to: MattKurtze5538

Hi Matt,

 

When you wrote "each load case as a separate DS then creating the combinations in separate file", it is not clear if you are manually creating the combinations in a separate file, or are you using the command "Results Options > Other > Tools > Combine Load Cases"?

 

Assuming that you are performing a linear static stress analysis, the "Combine Load Cases" command will "merge" the results from multiple analyses into one model. The "merged" results can either be added together, or put into separate load cases within the merged model, or any combination of the two. So I think this is what you want to do, correct?

  • model 1 results --> merged model load case 1
  • model 3 results --> merged model load case 2
  • model 18 results --> merged model load case 3
  •  ....
  • model n results --> merged model load case LAST

When viewing the results of "merged model", you can switch between the different load cases by using the "Load Case Options" panel (located on "Results Contours", "Results Inquire", and "Results Options" tabs.). In this regards, it is somewhat like using different design scenarios, but using multiple load cases is more efficient for switching between the different results.

 

 

Sincerely,
John Holtz, P.E.
Senior User Experience Designer, Simulation
Autodesk, Inc.

Current version of Mechanical & Multiphysics: 2013 SP1 (2013.01.00.0012 28-Jun-2012)
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Contributor
MattKurtze5538
Posts: 15
Registered: ‎10-27-2010

Re: Load Envelopes

01-03-2012 06:29 PM in reply to: INACTIVE_AstroJohn

Hello John

 

Thanks for the reply.

 

I am using the 'Combine Load Cases' command.  This works as advertised.

It sums the results of multiple design senarios. 

 

What I want to do is 'superimpose' the results of multiple design senarios, without adding them.  The envelope case would looks at the results from diffenent DS and display a model that shows the higest stress/displacement at each node.

 

ie if point A had stress of '1' in DS 1, '2' in DS 2 and '4' in DS 3. the envelope would display '4'

    if point B had stress of '6' in DS 1, '2' in DS 2 and '0.5' in DS 3 the envelope would display '6'

 

I hope I have made myself clearer.

 

regards

 

Matt

                                

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INACTIVE_AstroJohn
Posts: 492
Registered: ‎03-25-2010

Re: Load Envelopes

01-04-2012 06:28 AM in reply to: MattKurtze5538

Thanks Matt. That makes it very clear. We do not have such a capability at this time. Perhaps someone out there has a utility that can do that and would be willing to share it with others.

 

So that I know what we need to design, would you also want to know which model the maximum occurred at each node? Displaying a contour plot of the "envelope" in your example would show point A with a value of 4, point B with a value of 6, and so on. Would you also want to be able to display a contour or inquire on the points to see that point A's result came from DS3, point B's result came from DS1, and so on?

 

 

Sincerely,
John Holtz, P.E.
Senior User Experience Designer, Simulation
Autodesk, Inc.

Current version of Mechanical & Multiphysics: 2013 SP1 (2013.01.00.0012 28-Jun-2012)
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Contributor
MattKurtze5538
Posts: 15
Registered: ‎10-27-2010

Re: Load Envelopes

01-04-2012 04:19 PM in reply to: MattKurtze5538
Thanks John

That would be very useful, though probably not essential.
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