When to use Nonlinear Analysis?

Article by Irfan Zardadkhan, PhD, CSWE updated May 21, 2014

Nonlinear Analysis

Nonlinear Analysis

A Linear Static analysis can be performed on a problem if the following assumptions are valid:

  • The material is linear elastic, where the geometry will return to its original shape if the load is removed.
  • Deformations are small in relation to the dimensions of the model.
  • Loads and restraints are constantly applied to the model, without change in magnitude or direction. Also, the loads do not cause separate parts to come into contact with one another

A Linear Static solution is not valid if any of these points are violated. The relationship between the loads (generalized force) and the response (generalized displacement) becomes nonlinear, and a Nonlinear Analysis must be performed in order to get accurate results that reflect true-to-life behavior.

To determine if you need to do a nonlinear analysis, the following key questions should be answered:

  • Has the maximum stress exceeded the yield stress for the material? Or are any of the material properties modified as a consequence of the stress level reached?
  • Are the deflections large? (rough guide: if deflections are close to the thickness of the material then the deflections are large).
  • Is stress stiffening/stress softening occurring?
  • Are there dynamic or inertial effects?
  • Is a no-penetration contact area expected to change shape or size during the simulation?
  • Is a material experiencing creep or viscoelasticity?
  • Does the load direction/magnitude vary due to the deflection of the model?

If the answer is yes to any of the above then you should use the Nonlinear Analysis for your study

Related Links

Certified SOLIDWORKS Services available from Javelin

Javelin can help you to:

Find Related Content by TAG:

Irfan Zardadkhan, PhD, CSWE

Irfan holds a PhD in Aerospace Engineering and is as Elite AE. He contributes regularly to the SIMULATION and COMPOSER tech blogs. He has won the TenLinks Top blogger award for SOLIDWORKS. He has presented at local user groups and at SOLIDWORKS World.