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What is your actual assertion? That tools like FEA are needless frippery or that they just dumb down practitioners who could have otherwise accomplished the same things with hand methods? Something else? You're replying to a practicing mechanical engineer whose experience rings true to this aerospace engineer.

Things like modern automotive structural safety or passenger aircraft safety are leagues better today than even as recently as the 1980s because engineers can perform many high-fidelity simulations long before they get to integrated system test. When integrated system test is so expensive, you're not going to explore a lot of new ideas that way.

The argument that computational tools are eroding deep engineering understanding is long-standing, and has aspects of both truth and falsity. Yep, they designed the SR-71 without FEA, but you would never do that today because for the same inflation-adjusted budget, we'd expect a lot more out of the design. Tools like FEA are what help engineers fulfill those expectations today.




> What is your actual assertion?

That the original comment I replied to is false: "Good luck designing crash resilient structures without simulating it on FEM based software."

Now what's my opinion? FEM raises the quality floor of engineering output overall, and more rarely the ceiling. But, excessive reliance on computer simulation often incentivizes complex, fragile, and expensive designs.

> passenger aircraft safety are leagues better today

Yep, but that's just restating the pros. Local iteration and testing.

> You're replying to a practicing mechanical engineer

Oh drpossum and I are getting to know each other.

I agree with his main point. It's an essential tool for combatting certifications and reviews in the world of increasing regulatory and policy based governance.


Replying to finish a discussion no one will probably see, but...

> That the original comment I replied to is false: "Good luck designing crash resilient structures without simulating it on FEM based software."

In refuting the original casually-worded blanket statement, yes, you're right. You can indeed design crash resilient structures without FEA. Especially if they are terrestrial (i.e., civil engineering).

In high-performance applications like aerospace vehicles (excluding general aviation) or automobiles, you will not achieve the required performance on any kind of acceptable timeline or budget without FEA. In these kinds of high-performance applications, the original statement is valid.

> FEM raises the quality floor of engineering output overall, and more rarely the ceiling. But, excessive reliance on computer simulation often incentivizes complex, fragile, and expensive designs.

Do you have any experience in aerospace applications? Because quite often, we reliably achieve structural efficiencies, at prescribed levels of robustness, that we would not achieve sans FEA. It's a matter of making the performance bar, not a matter of simple vs. complex solutions.

> I agree with his main point. It's an essential tool for combatting certifications and reviews in the world of increasing regulatory and policy based governance.

That was one of his points, not the main one. The idea that its primary value is pandering to paper-pushing regulatory bodies and "policy based governance" is specious. Does it help with your certification case? Of course. But the real value is that analyses from these tools are the substantiation we use to determine the if the (expensive) design will meet requirements and survive all its stressing load cases before we approve building it. We then have a high likelihood of what we build, assuming it conforms to design intent, performing as expected.




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