Finite element method/crumple zones

Click For Summary

Discussion Overview

The discussion centers on the application of the finite element method (FEM) in crash test analysis, specifically regarding crumple zones in vehicles. Participants explore the complexities of modeling these scenarios, including the necessary software and theoretical background.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant seeks information on how to utilize FEM for crash test analysis and requests resources such as books and software libraries.
  • Another participant briefly mentions the relevance of non-linear dynamics in this context.
  • It is noted that the problem becomes highly nonlinear when materials exceed their elastic limits in crumple zones, complicating the analysis.
  • A participant explains that the nonlinear deflection equations involved are coupled second-order differential equations, indicating the complexity of the problem.
  • Explicit time-stepping FEM software, such as ABAQUS Explicit or LS-DYNA, is recommended for crashworthiness computations, with a suggestion to consult the LS-DYNA Theory Manual for further understanding.
  • There is an assumption that users of these software tools should have a foundational knowledge of FEM and continuum mechanics, as well as an understanding of plasticity concepts like the Von Mises yield surface.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and complexity regarding the application of FEM in crash test analysis, with no consensus on a singular approach or solution.

Contextual Notes

The discussion highlights the limitations of understanding nonlinear dynamics and the prerequisites for effectively using FEM in this context, such as knowledge of plasticity and differential equations.

Who May Find This Useful

Individuals interested in vehicle safety engineering, crashworthiness analysis, and the application of finite element methods in complex dynamic systems may find this discussion relevant.

randombill
Messages
81
Reaction score
0
I'm looking for information regarding the use of the finite element method (FEM) for crash test analysis and crumple zones? Basically I'm wondering what part of FEM do I use to make crash test analysis possible. I'm also looking for books on the subject or software libraries that can be used for it. Anything else would also help.
 
Engineering news on Phys.org
Non linear dynamics.
 
It's a very complicated problem. When things get into the crumble zone, the elastic limit of the materials is exceeded. The problem becomes highly nonlinear. Complicating all that is the fact that the nonlinear deflection equations are coupled second order differential equations due to the dynamics involved. It is not something you are going to learn in a week or two.
 
Explicit time-stepping FEM software, like ABAQUS Explicit or LS-DYNA, would be used for crashworthiness computation. The LS-DYNA Theory Manual can be found in .pdf form for free online. It's a good read. It assumes, however, that the reader has a basic understanding of FEM as well as some continuum mechanics. An engineer who focuses on crashworthiness would no doubt be expected to know plasticity as well (Von Mises yield surface, etc.).
 

Similar threads

  • · Replies 0 ·
Replies
0
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
6
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 7 ·
Replies
7
Views
5K
Replies
2
Views
2K