Solution Settings

Daniel Williams_21855

Hello,

I am new to SimSolid and have been running my analysis' using the Adapt to Stiffness solution setting. Reading through Altairs SimSolid online resources, we can use Adapt for Stress for general stress calculations. I changed my solution settings to Adapt for Stress and when I ran my analysis, the results were very different. When I had ran with Adapt to Stiffness, my structure was fine and I had no stresses that went above my yield stress. When I ran with Adapt to Stress, my entire structure failed and almost everything was over the yield stress. 

Is there a specific case when we want to run Adapt to Stress? I would assume that in most cases we would want to run Adapt to Stress since that is what we are typically interested when running an FEA on a structure.

Paul Leroy

Hi Daniel, 

By running an adapt to stiffness analysis, basically you run a custom analysis, with only 3 passes & no options. The advantage is that the computation is fast. It will give you a general results/main stress repartition, however you can't use the stress values displayed. 

That's why when you want to check is you structure fails under a certain load, you'll need to use the adapt for stress analysis. 

I already used the adapt to stiffness analysis to see the general load path prediction on a really large model (more than 300 parts, 500 connections..), to decid in which areas i wanted to do local models. In this case, the large model couldn't be computed with an adapt for stress analysis (at list on my computer...).