Dear All,

We are having a confusion here. We Modelled a Sample Frame (refer Picture attached) using weldments, and again modelled the same frame using part features (boss extrudes). With an aim of comparing both simulation resluts. Results are posted below in table format. Now, results are different we are not understading where the differences are coming from. moreover could'nt justify which ones are right. this is simple frame but for an actual real life component this could lead to disaster.

Please help us to justify which is the right way of doing it. The reason we did this comparision in the first place is because we could apply loads on weldment beams therefore we created our entire model in part model and ran the simulation. Also vonmises stress is not available im weldment, only axial stress and principle stress Then question was raised to compare the results.

Part model Result | Weldment Model result | |
---|---|---|

Deflection | 0.146 mm | 0.807 mm |

Stress | 10.2 MPa (Von Mises Stress) | 9.2 MPa (Axial Stress) |

Accurate is a relative statement. It is relative to the assumptions made.

There are less assumptions made in solid elements assuming you have a good mesh. But beams should be similar.

But relative to the real world, my guess is you have more assumptions than just that.

My recommendation would be to break out some equations and show yourself the software solves problems with beams and shells and solids in a way that match your hand calcs. Then start with solid elements in your assy and change elements to beams. You will find that eventually one connection or part is changing your answer. And you will know what idealizion assumption you need to be aware of when comparing to real life.

Another test now. Make a change to both models. See if the difference between solutions holds.

But overall, I wouldn't be concerned unless you want high correlation to real life. In that case, you have a lot of work to do to remove assumptions.