Project 1 - Simulating a BTMS

This is the biggest issue I think. I’ve seen so many models that were wrongly supported, wrongly loaded or simplified beyond reason! If you would analyze them, the “FEA” would work just fine, but the outcomes would be terrible (at best!). This is why you should really pay attention to details when you create, support and mesh your models.

I’m not advocating for overanalyzing stuff, but being able to predict what will happen when you simplify this or that is critical. Oftentimes such mistakes lead to tragically wrong outcomes.

Are the above case of FEA accuracy? To be honest I don’t know! I mean, in the end, you solved a “wrong model” and got the “correct but wrong” answers. Maybe this means this is indeed an FEA error! If that is the case, I would say that Finite Element Analysis may be dangerously inaccurate in the hands of the inexperienced engineer.

Imagine this is the strain distribution in an element with poor quality. The constant portion of the strain was calculated basically with no error… and that is most of the strain! The linear portion of the strain was calculated more-or-less ok, while the quadratic portion was poorly calculated. Overall, the accuracy wouldn’t be so tragic!

And there is another twist! If your elements are “small enough” definitely most of the strain in the element will be linear! Simply because strain differs in your model for sure, but it’s almost constant in a “small enough” area. This basically means you have a really good shot with the accurate results… even if the mesh quality sucks. All you need in that case are small elements!