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smr

How to Apply load case limits?

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Hi all, 

As a part of structural simulation of an helicopter wing, I have calculated all my lift and drag forces and submitted the job for max lift and drag conditions. I observed a max displacement of 5000 mm which in practical case is not possible. Since I gave only Elastic properties, this happened. In the process of understanding the BC of my problem, I found this tutorial "http://www.altairhyperworks.com/training/self_paced/os_linear/content/linear_3/PDF/Exercise 3a.pdf" similar to my problem..

 

Here they have mentioned a meaning full DESIGN Criteria in the problem. How so I include this to my simulation?

 

and for Static linear, my simulation result file shows results in 25 frames, deviations are minimal in first frame of the results... How do i extract result values from different frames (able to view results only for Min and Max values)

Screenshot (95)_LI.jpg

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On 7/28/2017 at 6:31 PM, smr said:

 

Here they have mentioned a meaning full DESIGN Criteria in the problem. How so I include this to my simulation?

Hi,

 

Not sure which point you are referring to in the pdf. Can you please point to the exact page in the pdf?

 

It is not possible to have intermediate results for a linear static subcase. You need to run a Quasi static analysis to extract intermediate results. 

 

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Hi Prakesh,

 

In the pdf  (attached a screenshot), on the very first slide.. under image "Model Information" is mentioned.

 

as a part of Design criteria:

- static U < 20 and stress < 70MPa is mentioned.

 

Is there a way to add these load limit while or before analysis? 

 

Thanks for reply,

Regards

Sachin

Screenshot (95)_LI.jpg

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@smr

 

That is the design criteria and needed. If that is not respected you need to either tweak the design or do an optimization. 

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Hi Prakesh,

 

Here is what I understood now, please correct me if I am wrong...

1. I define my goal (i.e design criteria), wing should deflect within this range and max stress allowed should be less than yield stress.

2. Now I calculate all possible loads, say set 1, set 2, set 3 

3. Create load and respective load steps to check whether the results are within the design criteria

4. Say set 3 results show deflection or stress beyond the range defined / assumed as design criteria

5. Now I either update loads in set 3, or neglect set 3 and use only set 1 & 2 for further buckling or any other required steps

 

Finally, Design criteria mentioned in the pdf file are for users to know where to stop increasing the loads further on the wing. 

 

Previously, I taught Hypermesh provides an option where user can input design criteria range and Hypermesh automatically stop the simulation (here set 3) when reached this limit saving lot of computational effort.

 

Thanks for clarification.

 

Regards,

Sachin

 

 

 

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20 hours ago, smr said:

Previously, I taught Hypermesh provides an option where user can input design criteria range and Hypermesh automatically stop the simulation (here set 3) when reached this limit saving lot of computational effort.

I think you are talking about optimization. You can impose design objective and constraints to optimize the design 

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